Mastering Voltage Drop Testing with Pete Meier and "G" Jerry Truglia

everyone to the last motor HT ST webinar of 2014 on a Saturday no less on a Saturday right glad you guys could join us before we get started I am Pete Meyer motor age technical editor and this is my good friend Oh Who am I she truly president of tea estate all right before you get really started a couple of things some of you may or may not see a chat box on the upper right of the player page that you're looking at for some reason we're having issues on our end seeing it so please if you have a question or comment use the discus comment box right below the player to put in your questions or comments keep in mind there is going to be a short one to one and a half minute delay between when we see something and you guys actually see it on your end so we're not ignoring you we will break from time to time to to answer those questions and take note of any comments that you guys offered but before we get started I want to say thanks to our sponsor for today's webinar automic Attica yeah live mechanical that's a company name s of Frankfurt based in Frankfurt Germany if you're not aware this let me get a couple of things for you real quick hits some of the highlights mail you may not know the name auto mechanic a-- but they've got 13 other shows across the cross the globe correct the biggest one is where they started frankfurt germany we just got back from the shows in Vegas yep right they were pretty big especially SEMA right right it was pretty big no doubt but you know gee if you take those two shows together and then triple that that's auto mechanic of Frankfurt big that's three four five million square feet of exhibit space they're like a dozen different buildings over there just is huge and this and this auto mechanic a show right here in the United States in Chicago is going to be in April this is really about technicians going to be a little bit different the biggest training event in the country maybe even in oral yeah I think one of water cups yeah I mean this is really something that makes the difference with that brand globally it's a connection between you guys the technicians the shop owners whether you're an auto repair or collision repair that's what people are coming here to do they want to meet you they want to know about what do you think about their products what improvements they need to make tooling stuff that you use around your shop going to be we have a bunch of exhibitors already signed up to be there so it's going to be a lot there to see but is G mentioned what I'm personally excited about because of help with G and some others as the training event that we're hosting at the same time and you know we've been doing the webinars now for four years Wow well I'm flawed folios yeah and one of the things that we wanted to do with these webinars was to make training and information available to all of you that may not have options of getting that information so when the opportunity came to do auto mechanic of Chicago we weren't try to do the same thing so if you haven't heard the news let me be the first one to tell you we have two thousand scholarships to give away to technicians so they can come get the training that they need now registration for this events going to be opening pretty soon it's going to be as G said held at McCormick Place in Chicago Illinois Marc April 24th 25th and 26th Friday Saturday and Sunday it's a very friendly venue to get back and forth from the hotel to or if you're within driving distance yeah I mean it's just you can't usually place even a fly envy oh yeah yeah for many where you know it's a Chicago is a big hub and just think about all the top instructors in the country are going to be all gosh you get John Thornton Bernie Thomason yourself Scott Nana Scott shot I mean you name it Gettys Anders John and ello I mean anyone who's any anyone in the automotive industry will be teaching here our buddy Wayne Colonna right we've got sixty instructors lined up and they'll be delivering over a hundred different programs over the course that two and a half days so guys if you this is your chance this is your opportunity to get some really dynamite training like I said keep your eyes open if you're not subscribed to our newsletter go to motivation comm for text just like it says up here on the top of the screen sign up for the newsletter just like you learned about this webinar today that's the same way you're going to be able to find out about when the registration opens you can get your hands on one of those scholarships you can get signed up and you can pick those those courses that you want to take and get to see a trade show aimed you know directed just for you just for you definitely find out you know what products that maybe you were interested in purchasing or how they work or whatever it may be there's going to be a sonic demos it's going to be informational seminars at the trade show floor we're going to have a place called career connect so if you're in a go illinois area and you're a student or you're a tech looking for maybe a better job you'll be able to look for one right there career connect at the trade show for and if you're a shop owner in that and a member of one of the local organizations that I have to be careful but yes but they will let you know who they are to invite you to participate as well so if you have openings you're looking for text here's a place where you can do that and even interview right there on Sunday right there on the trade show floor and another plus with ASE if you're interested in taking an ASE test yep you'll be able to take it at this particular job right and guess what that's going to be the second session for the brand new l3 hybrid certification that's correct if you've got that one it take or certification to renew during the entire course of that two and a half days is going to be a tough testing session available right there at the event so you can get that done in between classes or you know in the afternoon after your classes are over so yeah this is going to be the Super Bowl of training so you need to be there need to be there we'll hope to see it okay today's topic mastering electrical troubleshooting you know today's cars have become more more electronically complex I don't think anybody would refute that getting more and more so every year but you know the neat thing about it is all of these complex systems are not really that complex they still have to work in certain ways they still have to obey certain ones about certain principles in order to function they have to have the same basic elements and they're all tested very similarly so P basically what you're saying is get back to the basics and they're always true Ethel ain't always true but you guys are Washington notice that when you've had a problem and that you just racked your brain you finally figured out the solution and you end up kicking yourself in the butt because you know what it was a fundamental principle that that lay at the heart of your answer that's all right basics are key so if I could get our lovely Miss Doreen who is handling the camera action for us and of course we must recognize a VP preppy R respond the sidelines he'll be answering any questions he can as they come up and letting us know the ones that we want to discuss a little further as we go along let's talk a little bit about those fundamentals I know for a lot of you guys this may be review rehash with some stuff you already know but J and your training experience you know - that a lot of times it's a missing link somewhere there that trips guys up yeah you know unfortunately Pete in in our industry in most cases most Tech's didn't have a good foundation training experience such as electrical classes whatever you know like myself when I first got into the business I didn't take automotive in school I learned in in the city just working on cars and little by little I went to school later on to learn stuff right and you know I worked with some guys that took tin foil to find a short put around a glass fuse and so look for the smoke they come out yeah that was the doc about this back then but you get back to basics and understand electricity especially when I teach a class people buy expensive meters doesn't matter what brand they'll spend anywhere from a couple hundred dollars up to maybe six hundred dollars they don't use most of the functions on the meter because it becomes a glorified test light and they don't understand really how to use it when we say voltage drop or as I like to say VD they don't have a clue on how to do it right and this is what this basic circuit is all about you know what a power source as you have here a ground side the positive side a switch control a fuse and of course you need a load right and I think that's where a lot of people kind of lose sight of that you know we use a lighting circuit here in the diagram because that's something you can see you know where it's not working right you know it's not working right but there are principles of of troubleshooting a bad light circuit are the exact same principles you can apply to an ECM controlled circuit or any other complex circuit oh that's correct they all have to have a source of power they all have to have a load wherever the component that's doing the work they have to have a path that connects the two that's got to be continuous there can't be any breaks that squares got to be some way to turn that circuit on and off and there's got to be something to protect that circuit they all have the same elements correct right and if you master a simple circuit like this you know like a lot of students have brought me up vehicles that they had problems like say on the fuel injector most fuel injectors have 12 volts going to them key on engine running right and the computer supplies the ground now if you had an injector that stayed on all the time like I remember one vehicle that this guy had this inject to staying on all the time the vehicle was running rich and had no clue what the problem would they he thought it was maybe a bad ejector you know he thought it was maybe a bad computer now think about it what's happening there if we have power going to that injector if the ground wire is pinched and staying on is get grounded somewhere right a short the ground that ejector is going to be putting fuel in all the time sure he's lucky he didn't hydrostatically lock the motor right and that leads us to the great segue that leads us into our next slide there's only so many things that can go wrong with the circuit exactly if the path hasn't open somewhere that it's a not a complete path it can't flow current right and then the load can't work because I mean the load needs current flow in order to work though that I mean you know Peter I wanted to say something here all the years that I've been operating in a shop or been a technician no one ever came in and said could you fix my open they always call it a short okay and a lot of circuits are broken wires they are open and this is something that you need to understand between an open a short the ground as you have your shorter power and voltage drop or accessible resistant right it really is key in doing anything on that vehicle with the computer system or basic lighting anything power windows people just don't get it yeah and the shorts the grounds are kind of interesting you can have a short to ground but it's on the other side of the switch where would be grounding anyway we're not grounding at the point that the engineer Warren water ground and that creates something to stay on the last one excessive resistance correct and and I don't know about your experience gee but in my experience and you tell me if you agree the majority of the problems in electrical circuits that we find is due to some form of excessive resistance oh no doubt voltage drops you know I get a lot of stuff from different transmission shops auto repair shops when I say students these guys are my students professional guys and it's always a voltage drop somewhere whether it's water leaking down from a windshield going on a computer board whether it's corrosion in the back you know from moisture going in to a lens on a on a trunk light guess what voltage drop is a biggie or broken strands right because I mean we had we had a honda in here that had a couple of strands that was causing a whole problem on this vehicle okay now you'll get things to work over the customer had lights on in fact one of the texts at work here at the time he thought that it just needed a new you know a new battery or new light oh whoa whoa check everything when we touched the ground of the battery to the engine everything lit up and I think we did this a while back on one voltage drop webcast that we did and guess what it's getting back to the basics do you have a good ground that battery is the source the electrical source of that car and you need a good ground you get someone like Honda you get someone like Ford and Toyota they take their ground cable they strip a piece off and it gets grounded to the frame when that gets corroded or those strands start breaking well you're going to get problems like hard starting you know maybe your alternator is not working right or whatever you need to do a voltage drop test and that is the biggest problem that I see is really high resistance or excessive resistance on electrical problems yeah and they say if you guys backed out a little bit during so yeah so we're like giving direction the same time we're doing so okay I want to just add there to here's a little challenge for you I can't recall the right instructor to give credit for this I'm not taking credit for it but it will demonstrate exactly we're talking about about too much resistance in the circuit the circuit has to be able to carry that current load think of a starter for a while right and we've all seen guys who put those those quick fix battery cables aren't there the clamp strip the end of the cable and put the clamp on there you know and then put that on the battery and we've all seen the cases when you go to hit the key and as soon as you put the starter to it everything dies our little dials because the connections broke met that connection cannot handle the current load correct now if you take a static resistance test you'll measure the resistance be fine exactly so if you want to try this take a piece of starter cable measure the resistance of that piece of starter cable and either end okay then grind away about half of it measure the resistance again and then measure the resistance on one strand it's going to be the same but would you hook up at one little strand of wire it would go you can't be like a fuse it pop instead like Robinson like you burn up but quick also want to mention here a little bit Ohm's law let me the first want to tell you I don't care if you can do the math I don't care if you use it to figure out the missing value that's not what it's all about almost laws about understanding what the relationship between voltage resistance and current flow is and if you get anything at all remember this any extra resistance in the circuit no matter where no matter where middle the end the positive side the negative side is going to reduce the amount of current flow and that's going to be what's available to that load and that's what's going to affect its operation a more cellular and when we say load whether it's a light bulb or a blower motor you can get a car that's overheating okay or the air conditioner not working right because that blower fan is has high resistance in the circuit and cannot turn at the proper rpms right now you know people always say oh I'll put a new motor in well if we have high resistance in that why we'll relay how many relays go bad that people never checked right absolutely they don't look for it that's the belly drop is the best thing that you guys can do out there get yourself a good meter and you know we'll go over how to do that today yeah so let me roll this over here and if I could get our lovely camera operator to kind of homed in on our little display okay question time what was a sorry ways question current load or current flow okay let's see if we could be as specific as we can the load the load the circuit in this case the light bulb that's the resistance of the circuit that should be the only real resistance in the circuit yes all the connections are going to have a little bit even the wire has a little bit exactly but the load is what determines what the current flow is going to better begin Ohm's law correct gate and this is the load on that circuit so I hope that clarifies difference when we refer to current load or current flow okay and guys this is how I became more comfortable with the voltage drop is a testing that I want to encourage you to to go back and you view this webinar as many times as you need to to make this information yours and you want to be second nature to you in order to be effective at troubleshooting these electrical circuits and that's the skill that you absolutely have to have going forward in this business sure today's vehicle everything electric many computers on a car you need to get this basic stuff down very well so let's let's use this basic circuit to just demonstrate some things that we talked about so far ok basic circuit source right I got a path got a load so make make it all complete hey light works and it works the way it's supposed to correct right now we're going to use another light bulb just to simulate where'd you go oh yeah yeah sighs I don't know where you put that one weird and it could be anything any kind of resistance and resistance I guess we should stress it could be because there's damage to the wire it could be corrosion it could be a weak connection at a connector babe socket to be dumped it could be any bit common stuff right anything that cause excessive resistance so this is just to demonstrate what happens when you put extra resistance so remember the intensity of the bulb that you had just seen with one bulb and now look at the intensity of the light bulb for both light bulbs because these are bulbs of equal resistance that lowered it down and if we had checked current flow which would easily do with an amp clamp is going to be a big difference or we could even do it a meter in series well you know what I know is having the current flowed right I can see it when you're used and that's one of the nice things about using a lighting circuit to to develop your skill because you'll see the results when you may not see it in the fuel pump or the blower motor or the injector cell in a weight or whatever whatever other load that you happen to be working on okay so we know that this has got a current flow issue you know we know that what it was caused by in this case but here's what I want to stress all the voltage that's available in this battery is being used and it's being used while I had one load or the two but all of us getting used before it gets to the end of the circuit the difference being and why you're seeing that the first bulb has gone dim now is that because now there's someone else in the circuit that needs it share that's correcting so that means that the voltage is split proportionately see if you can wrap your head around this the voltage being supplied is going to be split proportionally to the other resistances in the circuit and it doesn't care if that second resistance is a light bulb or corrosion or a weak connection or a loose ground or whatever that case might be so that's the whole idea behind voltage drop testing using that that knowledge that voltage is going to drop across the resistor and if it's only the one true resistor is the load that we're worried about it should drop completely across that load right so that's the thing I want now we're going to take a look at that let's put it back to the way we had her and we'll start that up I'm going to turn the multimeter on here and let's not forget voltages pressure amperage is flow now when I first started doing voltage drop test this is the way I learned and we're going to show you a secondary method here in a moment but just so that you understand where we're at with this voltage potential in the battery we're going to measure that and I'm getting 12.25 is that better on the camera with the light on yeah we can see it okay okay 12.25 so now I'm going to check the voltage going to that load on the positive side of the circuit we're going to get right all the way down there to smoke in the better your of your vendor cover good see if I can see it with the light bulb going now that way bogan right right we get a reading there yes okay so you can see that on there on the meter a couple of tenths difference okay so I lose them a little bit here at the connector which is to be expected but now look what happens this is what I want you to see is after we get across the load to the ground side now the meter is reading it's like 0.03 from what I'm looking at or that's 30 millivolts 30 very very little always have that little imaginary zero at the end here of your meter so again you see that this is where we've lost the voltage drop the voltage across that load this load should be using up almost every drop right of voltage potential right and you're not going to have a perfect no it's not going to be a perfect zero because again we have other connections in the circuit and there is some resistance in those that's going to make up that 30 millivolts that you see correct that's that split proportionally that we talked about when you're testing the circuit that isn't working properly very first thing to do is check your battery your source voltage then check the battery voltage on the positive side they should be about the same and then check on the ground side and that should be almost nothing correct okay now let's see what happens when we put that extra resistance in the mixes will hold that up now that I can't say yeah now watch peeps go check at the same spot after the first load yeah so now we have what we know we have a problem right lights dim we know there's a problem the fuel injectors not working properly the cell annoys not hoping properly fans not blowing flow whatever they are not at all this is how you can find out very quickly where the problem is number one at the battery 12 to six four to eight whatever that says from here - namely number two on the positive side the load 12 to five so to have a little bit of voltage drop pressure loss from here to there because of the connections and then let me stress you want to check the entire path you want to get as close to that load as you can okay and then we're going to go to the other side of the load or look at that you have half six volts 70 millivolts so what now I'm going to ask the guys real quickly and it's going to take a minute or two for them to get their answers and I tell me guys what is that telling you what do you know now based on what we've talked about so far that that's that meter reading no longer 30 millivolts now we're at 6 volts plus what is that telling you and while it in here to see if there's any responses of that here momentarily about the proportion what what is the proportionate change in what causes the proportionate change in a circuit both is dropping proportional to resistance okay the query came up on clarifying what we meant by the voltage being used proportionally among the resistors if I recall and if I'm mistaken someone can correct me Kirchhoff's law I think is the official official law that talks about the use of the voltage across the circuit if I have resistances that are equal the each need each going to get an equal amount of voltage applied as you can see here and what we just did right these are both the same bulbs so their resistance operating resistance is the same and they're sharing the voltage applied the same correct now if the second resistance was only half of what the first resistance was then the first is going to get twice as much as the second so it's a proportional amount being used depending on the amount of resistance the other thing I want to stress here and please generate chime in there all the voltage drop issues that I've ever tested you know you'll hear instructors talk about this is the limit this is you know 2/10 3/10 5/10 depends on what circuit you are and that's all very good and true right but 9 times out of 10 if there's a problem it's not going to be a matter of 1/10 or to correct right it's going to stand out just like you saw this one stand out you're going to know right work that there's a problem so has anyone responded to the query that we had and there were various parts of this and said tells me the other vault is robbing voltage from the first ball guy so ed says one bulbs robbing voltage from the first pope the other one said resistance between the first vault and battery Navy kind of saying the same thing adding resistance assuming they were all people yeah and there are these Quran alumina equal both is correct and I want it and I want to point out that if you don't get anything out of this part of it again first step what the system voltage is second step reading the voltage on the positive side of the load third step read the voltage on the ground side of the load if it's not normal that's the side of the circuit that has the problem correct because now that we see that there's six volts measure here in the ground siding we know that the voltage should have dropped to next to nothing that's going us that thief whatever it might be is on the ground side of the circuit and what Pete's saying is forget about this other bulb being here if right if we're checking a circuit and you start here with 12 one number two we should drop everything there we of course have another bulb in series with it of equal resistance so the pressure here is going to be the same as the pressure here and then when we get to here we should have very little pressure left it should all be used up by two sides and what Gerry just described was how you find out where that son of a gun is hiding correct okay once you know which side of the circuit has the problem you start working your way back to the battery until you're reading returns to normal let's try that we'll go to the first Connection we have in our wiring harness okay we got six one three still got the problem will come down to the next connector we got six one two now we're going to go to the third connector and there we go we got 0.02 or twenty millivolts meaning of this allowed to use up everything right near the end right so a problem is from this point back between the last two points that's where the problem is and Jer you ever want your big baseball fan up right when you see guys getting taut between first and second and the two basement or tossing the ball back and forth trying to catch the guy in the middle that's how you find the problem in your circuit where you keep going down the baseline until your return to normal on your meter reading now you know you just passed that guy and you started heading back the opposite direction until it goes bad again and you narrow down the field until you home in on exactly where the problem lies right you know the other thing just maybe to clarify it a little more anytime you're working on a vehicle let's make believe this bulb is the tail light on the on the vehicle when you have that particular problem where the tail light is dim where are you going to go you can start check-in from the front of the car all the way to the back well that would be a little foolish if you take your meter or a power probe or jumper leads go to the battery first to make sure that you have source voltage 12 point to twelve point six whatever the case may be and then go to the load if you have 12 six go into the load you have no voltage drop on the feed side if it equals what you had there and if you're only down like Pete said a couple of hundred millivolts and eight your problem now go to the ground side if that side is up and not use it at all there's your problem for most of the circuits that you'll find yourself troubleshooting I think if you take these three simple measurements you'll know right away what side of the circuit has a problem none question yeah and I'll give you guys a noble one you know before GM went to lamp modules you know they used to run wires to the back of the car and power would come back and it would use a ground with a star washer in the back and that star washer g4 or two because they do grounds one two three four four would be one of the grounds in the back that particular ground was not only for the brake lights in the back and the third brake light but was also for the fuel pump what would happen to a vehicle is when you're only using one load you're not pulling as much on the ground right but as we put the brake lights on as we put the tail lights on all using the same ground what would happen to this car is it would start running funny the fuel pump didn't have a good enough drop of good enough speed to supply enough you'll share which was caused by a voltage drop and this is something that you would go back and check your meter go to the load why is that bold dimmer now why is that fuel pump and if you see on your ground side that a little sudden you got a high voltage reading and when you know we should be down let's take the GM little rule 500 millivolts I'm a 200 millivolt guy but whatever the spec let's say it's 500 millivolts if you've got a volt and a half here's your problem you're losing something on the ground side this connection is not good so now here's something else that I want to share that it's a very common mistake Jay and I we're talking about it earlier when we were asked to help someone electrical problem and the very first thing you tell us is why check powering grounds and they're good well here's how that you've been checking him okay let's just assume that the second bulb now in series this is our primary load this is the light bulb that isn't working right and the first one is now but excess resistance that we're on the hunt for what happens the guy this is the bulb isn't working right so what does he do he unplug the connector and then he measures the voltage at the connector oh look at that I got plenty of voltage so the power sight is good puts it back together doesn't know why it won't work right but what happens when we do a voltage drop test away we describe because you got to do it dynamically right so here we go there's number one and there's number two wow that's a big difference and make believe this bulb is not here so you would have on your feed side in this case you have a six volt voltage drop right there's high resistance which obviously we know is the bulb here but if you didn't know that this was in that circuit or high resistance in that circuit you went right to the load to the feed side and said my potential loss from the battery post is 6 volts I'll give you a really good example I had a GM pick up where the blower motor wasn't working the connector loose check for power at the connector had good power I can't be hit plugged it back in or won't working and dawned on me why should I should be doing what I'm telling other people to do check it with it plugged in with the motor on guys that's the thing about a voltage drop test that circuits got to be on has to be loaded I saw you get past the hood checked it then found that it was like next to nothing I think vector now traced it back to the firewall plug both effector back and sure enough there was like two strands of wire left at the connector block I have a question from the audience like on more testing or it sounds like it's more of a static test cold sounds more like what a dealer would have you do check and resistance checks now you know resistance check so I'm not saying the OES are wrong but they're working on new cars and he's a warranty claims they're hoping that something is out of resistance really crazy and you pick it up and it's done the real world is most aftermarket guys and most problems the best way to test the load is what Pete said make sure the load is on load the circuit and do a voltage drop test you know it's like a water pipe I like always using a water fight voltage I said before is pressure if we pressurize the pipe that's loading it up and you start looking for leaks and you got a little leak over here well you're not going to get the 40 pounds of pressure out of the end there if you got a 2-pound leak here correct right so you need the circuit load it up is the proper way I'm not saying resistance ohms resistance that's that not great right but you gave the example before with the battery cable share the same resistance on a full cable or on a couple of strands or even one strand yes there's no current flow going yeah and then and where do you call the line you're usually in the specs you see the resistance if it's under 221 ohms bail it but that depends on temperature you like the quality of your meter is so many other variables that come in I'm convinced that if this is the one test that you take the time to master make your own do it so it's intuitive when you know the meters telling you something's wrong if you if you do that here then you be the electrical go-to guy definitely you know and hey it's clean work use the time most the time and it's relatively easy once you've unlocked that secret and I think that's that's true for many of us at least it certainly was for me yeah I had to play with this for hours before I just finally went and you get that magic turn on the light bulb moment and then you just like wow that was just like yeah and you know simple we really don't get it because again it depends how you were taught like I said I didn't have formal training when I first got into the business so it was just watching people you know when test lights were big back then people touch and stuff and the test light you really can't see anything right it wasn't till later on with playing with a meter to understand and going through a lot of different classes that perform in a dynamic test voltage drop I can see where my problems lie and that's important and you showed one way of doing voltage drop by doing the meter from negative to positive are you going to show them the other way where you don't have to do the math or you're waiting for that no no that's a good what a segue you think we had this scripted didn't yet there's a very good points time to practice I'll give you a great example I had a PT Cruiser where the lights are just flickering like crazy and tried to use this method to check the grounds and so in the circuit and it wasn't by hook to scoped up to it to where I could see the variance in the pattern that I can see where the drop was but you know what when you're doing a running circuit when you have to have the engine running in order to operate that circuit then the voltage is not always constant so you may not always see those small variances so as you pointed out let the meter do the math and I'll take G's comment one step further I love his ouch use of his meter so we know that typically people would say that three to five hundredths of a volt 300 to 500 milli volts is generally the majority of the circuits on the car the acceptable range that you should be within well your meter when you set it on the millivolt scale that's usually right the over limit amount right so if you have a problem if you donate or le it's going to tell you oh well and let's just let's do that as an example now for this one we're not going to do the three-step method because if once you once you get comfortable and again make yourself up what you see here if you're not comfortable with voltage drop where you want to become more comfortable with it and practice those three steps that we just showed you and once you've got that down then let them meet or do the math because all we're doing is measuring the potential between these two points that's it that's all we're doing you're a pressure gauge exactly so if we want to do the same thing rather than have it set up the way we did before now we're going to check each side of the circuit separately one side on the positive and I'll get mr. Julie it'll hold that one there on the battery post for me and it doesn't really matter positive negative I don't it didn't really matter it just shows what their elegance may be right right pause and maybe you want to just show them the right way what the hell okay just like as a user if you but on the digital meter gentlemen it ladies it doesn't make a difference but just if you remember this what I was saying the class positive to the most positive negative to the next positive in the circuit right it just makes like so we come to the first one there's nothing in between here right to cause any type of drop shouldn't be going at any problems we're going to measure here and we get a reading 19.5% 19.5 millivolts next to nothing that's what we have in the connections right that's okay okay now what happens we move to the other side of the load and measure it again now it says oh well now if this bulb didn't exist and you were really checking this circuit here well on this saw well this side is our this side is our thief that's correct here's our load so if I went straight to the load just as we've been saying straight to the load and I measure there Gary's it there's the o L that means it's somewhere between my two leads somewhere between those two leads there's a problem right the pressure gauge is showing you you're out of the limits and it doesn't matter which side of the circuit the problem is if we lit the light bulb switch their roles and we'll move this one here got it I got it got that one now this is the the thief in our ground side and going back to the load on the ground side again we get the over limit yep oh well alright and that's like you like you they say you see that oh well it's ouch that means that is the side of the circuit where your problem is the meter did the math it just again the base runners I got guy on first base I got the guy on second base the problem is between these two guys and I just gotta bring them in together until I find out where it goes back to normal and then bring it back out to home in on where the problem lies like Pete said you know you can make this up yourself you got a battery around the shop or a booster pack or whatever you know get yourself a bowl put this together and start understanding that even if we simply just went from here we only had one bulb to start with just to practice voltage drop okay so here's the one bowl nothing robbing anything just to practice positive to the most positive negative to the next positive and you'll see our voltage drop reading our watt 29 millivolts 28 millivolts that's a good caption any and let's do the ground side now go negative to the most negative and positive to the next negative and you'll see the ground side has 30 40 ohms of resistance about 30 about 30 million millivolts excuse me thank you all right but now again that's and that's again a great example if this bulb we're burning dim or not at all and I just measured what we just measured where's the problem got to be right there the boy had to be in the component and that's not unusual here's a good example what about a fuel injector and it's not working is it we're not working because it was an electrical problem which is not working because it's just stuck mechanically okay I can perform this test if both sides of the circuit tested good and electrically there's nothing wrong with that circuit it's got to be a mechanical issue correct right but again at least three steps learn that method as one battery positive side load negative side of the load you should have the same thing of the battery on one side almost all of it gone on the other side if not the side it doesn't agree with that statement that's the side where your problem is or as we just showed you let the meter do the math set it on millivolts pop most positive to positive negative to the next possible is positive and then that should be enough your rating of millivolts and then the same thing on the ground side and then half and then you know your circuit you're going to know which sides got the problem so questions with some answers but there was a discussion about pulse width modulated control circuits how does that affect voltage drops that's a good question how does pulse width modulated signals affect voltage drop I got an answer for you what's it what is a pulse width control circuit is being turned on and off rapidly correct okay you will not be able to measure it conventionally with a meter but you can check it with a lab scope if you want to check the voltage drop on any pulse width control device you can do that with your lab scope because it's got to get pulled to ground back that's one of the things you're looking for on your lab scope trace when you're diagnosing any pulse width control device and that's why I always tell people when looking at a lab scope never put let's say it's a fuel injector never put or anything never put anything all the way at the bottom use one box or one grid division up so you can see very easily is it really being pulled all the way down right it may not be we could have a problem with the ground and there's our and today's scopes I mean you can really zoom in on just about any one of them on the market nowadays and seeing those issues no doubt and I'm going to talk a little bit more about some of these computer control because some other issues that we need to make sure we address like floating grounds and reference voltages and stuff man we're going to get to that and that was a good question because meters even notice is a good meter and his other brand meters out that are good as well you're not going to be able to do that so good question another question here dynamic voltage drop will dynamically the definition of voltage drop it has to be done on a working circuit current has to be flowing if there's no current flowing there's no drop okay but he was actually going at is something that's changing value this change to that max on your meters okay yeah max on your meter the only problem is dependent how fast if it's a pulse modulated signal mid max is not going to help you well I think a good example came of the PT Cruiser story that we just relayed the question was if you have your voltage shifting changing like an alternator that's changing as charging voltage to the battery if you do it with the first method that we showed you you're going to see that second voltage change and you're not going to know if it's too much or not right if you do that same thing with the second method that we showed you and even use the min max as Pierre suggested to record what the Peaks are then you may be able to catch it that way but if it's really something that you want to look at go to scope your scope will see it and you can see the difference between the two measurement points just like we're doing here I've got one channel on this most positive point and they have the second channel on the next most positive point and I can see that variance very easily on the scope in nanoseconds oh yeah scopes are way faster than a meter but no doubt from nearly everything that you're going to troubleshoot on a routine basis this is your friend this is what we just showed you method a or method B will help is going to help you find the majority of the problems agree okay definitely agree so let's let's try a couple of examples here and if I could get when we shove this out of the way okay and this is just going to take a couple extra notes because of the delay but I want to see if we get this so guys now you're looking at this the circuit diagram that we had up earlier we're going to use the type a method that we showed you first measuring first at the battery then at the positive side of the load and then at the ground side the load so let's just say for example one battery voltage make it easy twelve and a half that's the baseline your next measurements is positive side the light bulb here measure 11 1/2 good or bad I wait your answers and it'll take a unfortunately take a minute or so because of the lag in our YouTube stream but that's with a radio guys like because when someone calls on the phone and cusses they can dump them before it gets out on the air and gets in trouble from the FCC but we just have peer that doesn't have to worry about that right here saves us ok I would would sing the Jeopardy song but by the way that buzzing in the background since we have a vehicle in the background we have the battery on a maintainer the maintainer is maintaining a certain amount of voltage so the vehicle does not go that and we didn't tell you that in the beginning so in case you're a little buzzing in the background that's what that is so why you guys I'm alone that one I'm going to add in question number 2 nobody they'll catch up with one another question number two 12 and a half volts at the battery twelve and a half volts at the positive side of the load the light bulb a perfect zero on the other side the first question what was the point that the measure okay first question - reek - reek lera fight the first step is to measure at the source we get 12 point 5 volts here the second step is to measure as close to the load as you can on the positive side here the reading is only 11 point 5 volts is that good or bad I only got one from somebody okay it won't take that yes that's bad they have V big voltage drop we know that there's a volt less if we had measured it using method 2 we would have gotten the o L on the meter because we exceeded that that 3 or 500 millivolt limit and we'll say you know when they get the o L not to be afraid to just move 4 milli volts 2 volts it will show them the full amount absolutely yeah so that's something in case you were wondering you can still find out how much it is but what Pete's saying the way they made the meters and this is what I tell everyone you need a good meter because when you're on millivolts that's how you should be checking circuits for problems that's the voltage drop method if you go to oil or ouch you have a problem if you want to find out how much of a problem they just take the meter and move it down to regular DC volts and you'll see how much problem of pressure you're you haven't but to me I still got to fix that right do I really care how big it is no I got to fix the problem I got to find the unwanted resistance in that circuit in which we also demonstrated both ways we did it both ways okay so now question number 2 any responses twelve-and-a-half at the battery 12 and a half of the positive side but a perfect 0.0 when we move the lead to ground no answer actually I said one more okay very good very very good you guys are all coming back with bad on the very first question in 1.0 voltage drop yep absolutely yep that's what we would have measured and we move to the voltage scale correct on that second method I'll give it one more minute before we move on with that again if you're considering thinking about it twelve and a half at the battery twelve and a half at measurement point one positive side but a perfect zero point zero on the ground side what is the problem remember three tests and you can find out you'll know exactly what the problem is where it is you know it's not so much that the meter scaling question is well $9.00 per meter gives the same results as is $99 meter and let's narrow that down and talk about digital meters because you probably pick up an analog meter pretty cheap now it's not so much in the actual reading but in what the variance the accuracy of that reading is yeah you'll get a reading will it be accurate will be telling you exactly what's going on maybe in a major situation where the bulb doesn't work at all but it's not going to help you when you're looking for those very small computer control circuits that mess you up said once that opening circuit the other ones that open circuit involve okay so here we got some answers to the question here twelve and a half here twelve and half at Point a perfect zero on the other side okay the correct answer is yes there's an open in the load the problem lies in the load perfect zero there's no current flowing you're never ever going to get a perfect zero now I know exactly where the problem exactly because there has to be some resistance right if you take that one more step if we measure twelve and a half on the ground side the battery of the load rather okay now we know that the loads okay because that voltage went right through the load but again there's no current flowing there was no voltage drop the problem has got to be an open on the ground side of the circuit okay and these are real world problems you know it may seem very elementary or very basic to you but again this is how electricity works there's no matter what type of circuits on computer or a regular lighting circuit mm-hmm same slightly so we got to run through this real quick if I can just get an arene to zoom in on the screen Shaban all right okay zero volts measured at the power side of the load that would be the second measurement you take obviously the path to the load the positive side has an open circuit again zero perfect zero there's no current flowing and we're on the positive side that's got to be where the problem lies creig voltage measure on the power side zero volts measure on the ground side the load the load itself has the problem internal open but keep in mind you've got to be up in the load as close to the load as you can get here's a good example fuel pump maybe you can get the connector at the top of that tank but then you still had the point from that connector to the pump and back so the problem could be lying anywhere between those two points and how many times those connect is in the tank I've been issues so it may not be the fuel pump but you do know that there is an open between connector a connector be going to that fuel pump okay correct voltage measure on the power side of the load less than half a volt but not exact zero measure on the ground side the load itself has probably got a mechanical problem again that could be the fuel pump that could be an injector selling or any other solenoid for that matter electrically it's okay the circuits passing it's flowing current kind of question then another problem does not exist in other words you sang there 52 problems that doesn't mean there isn't something out there yes that's very true and we should stress there that what the comment was is that we had the perfect zero on the ground side that indicated us that the load was open but let's say you fix that maybe there's another problem you always want to verify any repair that you make that's what professionals do that's what we do correct once we made the repair we're going to verify the fix yeah always check the complete circuit correct voltage on both sides of the load there's an open on the ground side the circuit we covered that parasite and load is 0.5 volts or less than the battery voltage well then you know it's on the positive side of the circuit if it exceeds that on the ground side of course that it's on the ground side of the circuit you can use either method and again I want to can't stress this enough I really want to encourage everyone who's watching this now and later make up that little practice board and and work with this until you've got it until it's yours okay so let's try one on the car and see where we go and I will turn this over to to mr. Trulia I can get there okay so we're going to run we got here first we have and then you just heard that with a buzzing go up because we're sucking some more juice so we have the lights on and so far if or any of you can kind of move it over to the lights the headlights on a car already won so beam looks pretty good right looks pretty good park lights are good try high beam high beam oh wow I noticed something different I can see right here that this light is brighter than that light so this is a real type of problem I can come into your shop how do you know where the problem lies is it a bulb well I would seriously doubt it so what's the first thing you'd want to do we'd want to take our meter yep we're going to use a clamp here up and we move this laptop out of error netbook or whatever the hell it is and the first place we always start is at the battery so I'm going to put this clamp on for now I'm going to measure my battery voltage on my meter DC volts and I got thirteen and a half volts okay now there's a couple of ways we can do this I can now take this lead and remember I have thirteen and a half volts I'm going to switch into a back probe and I'm going to go down to this headlight of course being is blind and old as I am I need to put a light in here and I'm going to back probe the different wires I can't see what we got anything there we have point zero one or okay let's try the next wire three wires to go two wires more other point zero six really getting read on that one and if you're all the way in there or not and with that I think you're getting just a ghost voltage right there yeah again trying to get past the weather pack on here this is kind of thing we deal with all the time daga nothing yeah you don't have contact there it's like point zero zero you only grab the let's let them in but okay nothin Sam right in there still weapon not really it just bounced around a little bit although nothing there either and we get a good bite on that terminal again when in doubt always go back and double-check make sure your leads and stuff we're working good yep 13 dots there that's a people now that were the fact 4746 there zero for ten nineteen ten nineteen so here's my feed coming in on this side and if we did a voltage drop test from the battery to here we have ten we have ten something air or we can do this Pete we could play switch the clamp positive to the most positive don't worry about the black clamp because settle over the red clamp is and I'm taking the negative lead now and I'm going to that same terminal that we just had there and if we move that to millivolts first remember doing voltage drop it says hello now flip it down to voltage and I can tell you Pete we have one vote 562 volts and millivolts okay so the meter did the math if you took what you just had the 10 6 whatever was battery it's about the same as what you're seeing now the meter did the math it's measuring that potential between those two points just on the positive side of the circuit and now we know where the problem lies somewhere on the positive side of the circuit there's a thief yep there's no doubt so that's doing a volt to draw a drop on a real problem here and again now I'm going to plug the headlight back in so you can see and I don't know why I've tried doing it this way again I'm back probing it yeah see if you can pick it up anything that's the thing you're not quite getting through there that seems like I'm in there but I guess I'm not and that's a good point when you guys are back probing it's very easy to have your probe especially the very small probe tips deflect and go off into a cavity that you're not intending it to go into yeah you're off that's not unusual sometimes you can use like a piercing probe in order to get a good connection on there if you're looking for that voltage drop but if you do that make sure that you seal the hole you made before you send it back out in the road there's electrical liquid electrical tape you can get from your auto parts house works very very well clear nail polish works really well pink nail polish works pretty good but your guys at work will probably look at you funny you know if you have that in your toolbox so I got thirteen on two of them now thirteen right yep thirteen yep and 320 millivolts yep and now my light is not working at all boom thank you oh did you kill our headlight yeah I got nothing here you got no no headlights now hold on I think I see our issue I knew something had to go funky when I got that 13 volts okay there you go yet high and low beams yep now you're out on the right slow yeah right side of the car my left looking at 320 millivolts is excessive resistance they're going on but for a big thing like a headlight you're probably not going to notice all that much right I guess we really want to cheer like in this example you know when you're when you're looking for a problem let's say the headlight didn't work automatically low beam just rather just the high beam is out low beams working probably a bulb and like this would go right ahead and throw a ball minute and then when we find out that it wasn't working that's where this test comes into play checking the battery then checking this positive side the circuit and then checking the negative side of the circuit or as you pointed out most positive to the next positive using that over-limit function so you get that warning if you exceed that amount as it turns out when you go back to the voltage scale it's actually about a bolt in half right did all the measurement for you but the meter does the math for you is going to tell you what is between the two leads and on a functioning circuit with no problems there should be very little credential measure between those those those leads and that's really where I want to try to stress with this particular webinar and ID's a big fan of the same topic knowing how to quickly determine what side of the circuit has the issue is 90% of babble once you know the problems on one side of the other then it just becomes a matter of pulling out the schematic seeing what shared what's unique and then tracing just getting at first and second baseman to start throwing the ball back and forth until you homed in on that guy and tag them out correct hey we have some warm-up board here that I want to share this is actually made by our good friend Bernie Thompson over to automotive test solutions and it is a electrical test for it it allows G to create a multitude of various symptoms and what we want to try here is again setting up some issues on the board we have the test points for example here by the bulb you can see I've got a ground sight on the black negatives positive side on there red and it's laid out just as if you're looking at a printed wiring diagram just got the controls it's got the circuit protections got everything that you would have on the car but rather than us trying to poke through the weather seals or get to something or have an issue like we have here we'll get a nice clean connection you'll be able to see the same results that you would see if you did it this on the automobile right so let's let's let's drive something normal yep let's try to normal first and the first thing again to do is go to the battery and we're on positive and negative and Dorine could you see that voltage on the okay so we got 12 volts 330 millivolts now I'm only looking at this particular circuit forget about everything else you see just this one bolt if I want to see if there's a very drop I always go to the load so if this was the taillight in the back of the car or in the case here where we had the headlight I'm going to go to the feed side to see and it's two ways to do this we can go with the negative store on the battery and a positive there and it tells me I have 12 volts 290 millivolts now I would have to remember the last thing I just had right because I have to write that down write this number down and do the math right or I can go this is the other method positive to the most positive negative to the next positive and move my meter to the millivolt scale and it's forty two point eight millivolts exactly without me doing any math okay meaning we have some sort of resistance here in this wiring in this switch but that's good isn't yeah that's and that's an honest except that's like nothing to worry about you go and you're going to have that the wiring the connectors the context is everything in between those two points has a little bit right but again the majority that the vast majority the primary should be that load whether it's a light bulb of motorists Illinois whatever it might be on the car that's the primary source that's where that voltage to drop and something else has you just made a point o that we really need to make sure that all of you understand you've got to check the whole path Zhi pointed out something like a taillight or tag light or something on the back side of the car you can't put your ground of the body ground and then go to the load and expect to have a thorough test because what's that body ground connected to the whole body of the whole are right I decide awake all the way back to the battery and that's why you see the cables that are from the battery to the body and the battery to the engine to make all of those those are all ground points but you've got to go all the way back to the battery if you need to make up a 20-foot piece of wire that you can use as a test lead to go along with your multimeter do that because that's the only way you're going to going to be accurate for you they can make good fuse leads or they can use a power probe or whatever but go all the way from the sauce like I'm doing here now again this just makes it simple so again I'm on the battery now let's check the negative side here's my ground side good I got negative to the most negative positive to the next negative my meter is on Mille volts DC and I got 39 millivolts that's very good isn't it now I'm going to switch this off and we're going to go over what peak did before with the battery in the bulbs this is a series circuit and you can see someone may go oh well those bulbs look bad now maybe yes maybe no what we can do is do the same thing we did before positive to the most positive I'm going to go to the first load and I'm going to see I got thirty point two millivolts now that's my breath to drive right it's good yeah but what's going to happen if I don't understand a series circuit and I take it and I go to the next load to to say oh well isn't it these bulbs are of equal resistance when I switch this down I'm going to get about six volts six volts three hundred and twenty millivolts so I know that this circuit is good it's splitting it in half isn't it well that's what we talked about earlier right that's that's it's because they are equal resistance then the voltage is going to be split equally between them but it's in proportion to whatever that resistance was if the first bulb was twice that at all second or then the first ball was going to get twice as much as the second second bow so and and do I kick you know when it comes right down to it do I care I don't care all I know is this primary ball that's the load that should be using it up if there's somebody in between there that's getting a piece of that action you know define like this guy's doing taking six volts away from the ability for the second bulb to work that's the problem that's what I need to go back and find cause you would take that same lead if we back up now bring that that first baseman back to the second okay still got the same problem exactly so we haven't caught that thief yet and then we're going to come back to one more step back to normal it's got to be between those two testing points it's got to be got to be and once we know where that point is it's a simple matter of affecting the repair correct and when you're testing this guys don't go crazy I mean don't don't start opening up the harness just so that you can make it an equal links go to the common areas go connectors go these the first easy things first yeah you might find a chafe wire up underneath the rear seat but you know don't don't immediately pull the interior the car out to go looking for it I agree those initial contact points first and we have a question Oh God you know I think most of them they are going to be listed as series we care about our kids to the effect of how especially power is delivered to different components for example you may have one power feed to every interior light in the car exactly okay I knew being branch and then branched off from there as far as I'm concerned if there's one load that I'm testing whether it's a dome light or it again it's a motor or whatever it is it's a series circuit with one load correct okay not with two this is this is set up here to demonstrate the impact of adding the extra resistance to a sort to a circuit you know this again it's a test board it's a learning aid and and it's something that you should know because that could be voltage drop in the circuit that is voltage drop mister and there are some cars that use high water to light bulbs in the taillights for example and when a brake light are one of regular taillight goes bad they use for example Canon series circuit brake lights to give the same illumination while they turn on annunciator but they're actually using the brake lights in series as a taillight to keep you legal Wow until you get things right okay so that's up here our resident BMW expert explained how some euros use that as a as a fail-safe method I got another one for you in fact we use this as a challenge a few years ago of motor aged Jam cooling fans high and low speed oftentimes the reason they have a high and low speed is that when they want high speed is one meter I mean one fan working all by itself when they want to turn them both on and run them at a lower speed those motors are in series with one another and it's built in voltage drop and there are other examples of that on the carpet DRL are in series that's not universally true but yes VR else could be series now definite so there there are examples of series circuits on the car generally designed they're designed in both as drops but for the most part if I'm testing why something's not working that's the number one reason I'm not testing electrical circuits for the fun of it note I'm working on a circuit it means because I think there's a problem with it and I want to know what tip this just helps you understand something now let's look real quick because we're getting on here in time you know I always say when teaching a class your brain your eyes your ears your nose and your hands are very important tools and I won't even listen and look at the intensity of the bulb listen to the sound I'll shut up for a second listen to the sound of the motor that wasn't a second okay two seconds now listen to that can you hear the difference can you see the difference let's say this car came in your shop the fuel pump like that example I gave you before and watch this remember I said that GM car that had the problem with G of 403 listen that's the mail you notice the sound of the motor now listen again now let's diagnose this put a meter on millivolts or first on volts to make sure you got a good connection at the battery okay about 13 volts let's go positive to the most positive let's move this and let's go right up to the motor and I have 550 millivolts voltage drop go into that motor now that's a lot but is it going to slow it up that much it's two sides of the circuit this happens to be the feed side now let's check the ground side let's take negative to the most negative and let's go positive to the next negative notice it went well and let's turn it down to the voltage scale for a millivolts that is my main problem I have five votes 30 millivolts voltage drop and that stress is what we said earlier you're going to hear a lot of instructors stress to two point two point three whatever but nine times out of ten if there's a problem it's going to this is five volts this is a huge huge variance automatic right away you know there's a ground side problem between those two test points yeah right no doubt and you hit the nail on the head before saying let's not worry you know on a computer problem like Pierre hotel if you're on the BMW yoga voltage drop of probably 60 or 70 millivolts on a computer circuit you're going to have problems most cars and they can take 100 millivolts or so on a computer circuit non-computer circuit I've seen some five six hundred millivolts like you can see on a headlight you're not going to notice that like this motor now watch this look at that voltage drop of 5 volts I'm going to change something look what happened to all voltage drop we went down the motor is louder we're down to 172 mm now you got a good working motor don't you not like this where we have the problem hello Firebolts well you know I got to ask you if we know the problems between here and here where were we move the next where we would move second base to start homing in on where it is we got to go down that wiring to see where it is we can move to the next ground spot so this is indicating on the test board a body ground okay so the problem is between this body ground and the battery ground so I'm looking at a loose connection or a corroded cable or something like this and this is very typical guys if you have a very common for the ground cables to get corroded get weak it bad have that excessive voltage drop built into them and it does exactly what you see on the board you can hear the motor running slower you can see all of the lights are dim when you start seeing a bunch of weird stuff going on usually it's a major ground that's a problem and we could fix major things I've had some cars that won't start and you go out there and you take your test light or you take two meter and you touch the engine and you go hold it the ground on the engines giving you 12 volts just like the battery so what I do is I run inside and get the battery cables I make believe is a battery cable I go to the negative side of the battery which this is important so I'm at the battery negative even though that was another negative or just put this here and what I do is I temporarily make the jumper cables another ground and I'm going to put this ground right here and take a listen okay it basically solved the problem is foot here yeah but we'll restart it up but point taken I mean when we put when we force apply to good ground between the two points the Demeter was telling us the problem existed in it went back to working the way today without hitting anything here's my ground we could see the voltage rating take a look at the voltage rating here's a tall that's my jumper cable alright so in other words I had a problem with the ground going to the back of the vehicle or the chassis ground this is something that you could practice and and really get good at because when you're on a vehicle you really need that same setup you know Janus and that's because like you pointed out we're kind of getting close on time I want to be able to take some questions from the guys who are watching and thanks so much for taking some time out of your Saturday number one to come and hang out with us and participate in today's webinar really appreciate it and also let us know do you like Saturday's better than that by all means let us know you know if this works better for you we'll certainly take that into account when we plan for next year's webcasts but you know guys again if you can perform a couple of a tests and then know exactly where the circuit problem lies positive or negative whether it's not a circuit problem it's a mechanical problem if you can you can find that out so quickly so easily most guys don't have a problem with learning the technique I was certainly one of them I know put the lead here I know to put that lead there but when I got weird numbers on the meter as you pointed out the first time you see your meter laid on ground and on the ground of the car and reading battery voltage that tends to throw you off it didn't me and it will you if you're not that comfortable with it yet the meters trying to tell you something any number over that over-limit is telling you there's a lot thief in the mix there's a problem somewhere the early example with using the battery and a couple lightbulbs easiest way for you to start understanding where you put your meter leads what the meter is saying and what because you're creating the situation you already know what's wrong and then you go to apply it to a car I guarantee you the first few times you put this to use rather than that pull the plug out and you know see if your test light lights or need that not so let's see the results see how much easier it is for you to fix things electrically you'll be as convinced as I mg is that this is probably the most important testing method that you can master there are others and we've got a lot of stuff out there to help you with some other techniques that will help me even more but this is a fact this is a foundational test that you did you really need to master yeah and you know your meter needs to be like your your hand like an appendage you need to know how to operate this thing good especially on millivolts and volts when you go to that battery and like I said before and you're going to take this and check the battery first and of course if I take the lead and I check the motor and if I had 12 that's here when I'm touch your ground I got a problem so what you could do is take your battery cable leave your black lead on here but disconnect the battery cable and be careful on a car that has a whole bunch of pretty sets that you don't want or anything like that which is keepalive memory and you don't have a scan tool that's needed baby but do it on a vehicle that you know you can get back when you take that cable off and you touch the ground to the alternator or something and you get 12 volts then try taking a bunch of resistors or little strands or something with resistance a bulb use the bulb and stuff and put it in between watch that voltage levels start to drop and then when you put it back on of course now you're not going to read voltage anymore that is the same thing we just did here on the test board and that honda i said earlier on where a guy thought he needed a battery it was the ground cable was totally corroded that's one that i owe you a story on yes i forgot they were remembered it's all my computer any questions coming in that we need to address all right we have a few things to wrap up a few thanks guys that we didn't touch on computer control circuits checking power and ground of those floating grounds what they are but guys motor acecomm you'll find a lot of resources there same with the TST website a lot of resources there YouTube if and if and if that doesn't work for you send us an email it reach out to us on Facebook Google+ Twitter wherever your personal little hangout is you know you'll find us there and we'll be there to help you as always okay wrap it up course jeez main job the thing it keeps it you know bills paid the lights turned on is there a TTS if see if you have any highlights for us there well as they're always doing different classes everywhere if you're interested in any type of training whether it's at your facility or you feel like flying out here we do different types of classes from hybrids to basic electricity and basic gets pretty involved just give you a buzz or an email and be more than glad to answer your questions and of course the organization has been so foundational and helping me help you guys that's that's the organization's G is president of and of course our answer man behind the scenes Pierre VP in the delivery cameraman or camera person person waiting for this night TST all kinds of good stuff going on there you got anything on the immediate calendar for rougher guys around oh we're probably going to have John and Noah coming out be doing a class for us sometime in January we'll announce when that is I spoke to John today and look for some other stuff different webcasts we'll be doing our top tool awards coming up soon and if any of you people are in the tool business got any neat stuff that we haven't seen send it in it's not only myself that looks at it but our TST board we play with it on cars to see if it's good or bad or whatever don't be insulted if it's bad we won't mention it we're just sending it's cool if it's good we want technicians to know out there that it really is a good tool and we've helped quite a few different companies move some product out there so and it's all about open tax in closing guys I hope a lot of you will be able to take the opportunity the good graces of number of corporate partners and the folks at motor race training and Meza Frankfurt again we were able to come up with 2,000 scholarships to help men and women who need to get the training that they know they need to make that happen you know you got to get yourself to Chicago you got to find a place to stay set up a tent the park whatever you got to do to make it to Chicago April 24th 25th and 26th registration is scheduled to open very soon I don't have an exact date for you but again just the way you found out about tonight's webinar you'll find out about that get get on get signed up if you'd only come for a day or two I think you'll find that the rates are doing well you know life you know as conditions peak we work very very hard long hours we have a hard job and if you don't educate in update yourself you're going to evaporate so you need to take the time you owe it to yourself to take three day vacation to learn right get out from under the car all right down to do it in yeah and Chicago is a great place it really is yeah come out to Chicago to order Mechanica see a bunch of great people remember you not only learn off instructors we learn off each other speaking I mean that's how Pierre and myself for years and rtst

Channel: TSTseminars

Views: 106,202

Keywords: Peter Meier, Pete Meier, TST, ATTS, Automotive Technician Training Services, G Jerry Truglia, Jerry Truglia, G Truglia, Voltage Drop

Id: YaYtCVBodpw

Length: 86min 45sec (5205 seconds)

Published: Wed Jul 08 2015