European & Asian Vehicle Air/Fuel Ratio Sensors

[Music] [Music] [Music] [Music] [Music] [Music] [Music] [Music] [Music] [Applause] [Music] [Music] [Applause] [Music] [Applause] [Applause] [Music] [Music] [Music] [Music] [Music] [Music] hey welcome everyone into the NGK tech garage thank you for being here today looks like the chats already rollin this morning really cool we have people from all over the world on here and somebody had mentioned in there that there's no borders when it comes to training that's awesome to hear you know we have training from people here from Uruguay Chile Romania all over the world so it's really awesome thank you guys for joining us today I know with the time change thing sometimes it's difficult to catch a live class but really appreciate everybody being here so today we're talking Euro and Asian wideband or air fuel ratio sensors and to be a hundred percent honest guys a lot of what we're going to talk about today or what we could talk about today was covered in the last wideband class wideband or air fuel ratio sensors are very similar when it comes to domestic Asian or euro in terms of the sensors actual operation now you're gonna have differing voltage values or specifications or testing parameters or the way that the the PCM uses all that information but the operation of the sensor will be very similar when it comes to five wire wide bands or four wire wide bands they're very different sensors and we're gonna get into looking at a four wire sensor on a this is a 2006 Lexus is250 with the 2.5 liter v6 in there and then also we're gonna look at a five wire on that BMW sitting back there that's a 530 with the three litre straight-six in there so before we actually get into looking at these I wanted to show you guys something that we've been working on here for quite a while it's our training portal that we've created so if you head out to and you don't have to do it right now but if you head out to NGK tech portal com you're gonna find our training portal now currently what's 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this is going to be constantly growing I'm gonna be constantly adding training to this but right now we're you're we have ignition training sensor training and product training so we're really going after a system based approach section 1 & 2 both will cover system type of training and as you go through your life to complete each one in succession you have to pass the test on on 101 to go on to 102 and pass the test on 102 to go on to 103 there's gonna be a pretest and a post-test that you have to take and then they'll just be a short 10 to 15 minute video or so in the middle there where you're gonna watch you're gonna learn something about whatever that title was then you're gonna take a post-test if you pass you move on to the next one so we're gonna keep building upon this as it grows we're gonna eventually add in some sort of certificate type of thing but it's just a way another way to get access to training that's maybe not YouTube this is something that that you're able to to get to and use and it's free of charge and we just have a lot of really good ideas that we're gonna be putting into here and including into here so right now it's it's kind of very young but there's a total of what 15 classes right now and that will continue to grow as time goes so check it out there is a link down in the description down below in the video description here again that's NGK tech portal com or you can find it through a link on the NGK spark plugs website alright so let's see how the comments are thank you Keith for linking it in the chat I appreciate that alright so let's get right into it I do have a PowerPoint today that's just going to be kind of showing some specs and some we're gonna pull through it pretty fast but it'll be up on the screen so that you guys can always go back and look at it in the future it doesn't seem to be wanting to play nice right now let's try this one more time can't mine alright let's try this way okay now we should be good so we covered this exact slide last week just basically calling out what exactly a wideband sensor is it's a sensor that's going to monitor a wider range than a standard o2 sensor would a normal action sensor is only gonna read your fourteen point seven to one it's only going to understand what storchiometric is our air fuel sensors air fuel ratio linear UE geo wideband whatever it's being called is going to read significantly richer and significantly leaner and it's going to be able to tell the PCM exactly where this engine is at at that exact time so it's gonna be post combustion fuel control the exhaust gases flow through the exhaust pipe the sensor picks it up determines is there an excess of oxygen or is there a lack of oxygen that information is sent into the PCM to dial in fueling for the engines so instead of knowing it's either yes it's it's lean or no it's rich now we're able to know exactly how rich or how lean it is as long as it falls within those parameters it also allows us to stay longer in closed loop and it responds a lot faster so this is a four wire sensor this is what we're gonna cover today on the Lexus you can see that it looks very similar to a normal oxygen sensor it's got two pins for the heater circuit and then it's got two pins for the signal circuit it's going to operate like a wideband though it's gonna look like a narrowband oxygen sensor but it's going to operate like a wideband sensor fact I have one right here looks exactly like a narrowband sensor for the most part except it's going to output a value that's going to be directly related to the air/fuel ratio now these sensors get very tricky for dying because we're not gonna be able to watch them as closely like we would with the five lawyer that we showed last week and that we're gonna show sorry two months ago and the what we show on the BMW later so we do have the ability on this for wire in this Toyota here to read roughly down to nine or ten to one and then all the way up over twenty to one in the lean-to rich scale so this this graph right here is a perfect representation for you guys a standard good old narrowband oxygen sensor has that switching point right at 14 to 7 anything richer or anything leaner will respond as low or high where our air fuel ratio sensor is able to respond accordingly so the voltage will change depending upon where the air fuel ratio is but this voltage here is and I think misleading is probably the best way to say it because we're not actually going to be able to see the voltage output but we'll be able to see it on a scan tool our for our operation we're still using an action I am pumping circuit just like our five wire sensor is we're pumping o two ions across this is or Konya element we're basically measuring the presence of exhaust in the excuse me the presence of oxygen in the exhaust gas and then if there is a excessive amount of oxygen we're gonna pump that o2 out if there is a lack of oxygen we're gonna pump oxygen in and that's all going to be dependent upon the reference air chamber that's over here whatever it takes to pump that oxygen across here will be monitored by the PCM and that's gonna directly correlate to whatever our air fuel ratio is again it's trying to maintain that that stoichiometric fourteen point seven to one basically just leveling those oxygen ions across that element that creates or requires a current flow to pump those ions across so on a four wire sensor we're able to see that now the downside is we're working with a very very small amount of current we're in very very low milliamp current to make this happen and that happens inside of the PCM so I've tried to put a small amp clamp on here and was unsuccessful in noticing any sort of change in the milliamps there was too much noise coming out I was unable to see any change when this thing was run rich or lean but we'll show a little bit more with the scope in just a minute again here's our five wire sensor we're gonna find this one over on the on the BMW I'm just gonna briefly explain it because I did explain it pretty in-depth last time but we basically have a normal oxygen sensor here that's the nerd cell and it's job is to maintain 450 millivolts or the stoichiometric point right fourteen point seven to one then our pumping cell is going to pump oxygen ions in and out of the measurement chamber to maintain that 450 millivolts across this nerd cell so we'll see on the BMW today we're gonna see that this nerd cell might change a little bit but it's relatively steady and then we'll see the pumping cell working as we run that thing rich or lean failures went over this last time but of course we're looking at a slow responding sensor agent contamination can really cause our sensors to fail of course circuit failures wiring rubbing through chafing through somebody not putting it back where it was supposed to be and it melts on the exhaust manifold a lot of those kinds of things heater circuit failures is actually what this sensor is right here and then of course physical damage if you drop a sensor if you I don't know if you hit an exhaust pipe with a hammer or something pounding a muffler off these are ceramic inside it's possible to crack that ceramic cause a sensor to fail now this sensor did come out of this Lexus right here I thought it was going to be something cool unfortunately it wasn't very cool of a diag it was really straightforward it has an open heater circuit so the way that we're gonna check that on most of our sensors you're gonna find the two light colored wires to be the heater circuit so I have two black wires on here so I've just hooked up two pins here we're just going to do a resistance check across there and it should be usually a couple ohms different sensors will have different specs depending on the heater element but what we're looking for here is a few ohms of resistance and as I hook the meter up and show you guys we're o L right open circuit now what this looked like on a scan tool and it was being diagnosed this actually kept bank to driver side on this engine Bank to in open loop because when a wideband sensors heaters failed it will not the sensor will not function these things need to maintain a temperature higher than the exhaust gases are able to get the sensor so without heater operation the sensor will not function and it'll usually maintain open loop on that bank and that's what this car was doing we had one Bank an open loop one Bank and closed loop because this sensors heater had failed I have a known good sensor right here will do the same thing I'm gonna pin the two black wires and I think this thing came in at like two ish two ish ohms of resistance we're coming in at 2.7 so that's gonna be a known good spec on this four wire sensor that will find in Toyota models but again that might vary a little bit depending on the sensor depending on the heater type that's in there but that is pretty consistent in that two to four ish range now if you're questioning what your sensors resistance is supposed to be it suggest you give our give our tech line a call they'd be more than willing more than happy to help look up that sensor number and get the actual heater resistance spec for you so just give them a call you can find the number out on NGK spark plugs website NGK spark plugs comm and then just look for the contact us click on technical and you'll find that number there now when it comes to heater circuit failures this car probably on the BMW probably on just about every wideband air/fuel ratio sensor style out there when a heater circuit fails the heaters most of the time shut off now we played with this a little bit in the last class but this sensor when the heater circuit would go open the PCM would stop commanding ground we would so power flowing in there's no real there's no stop in addis it's run through a fuse run through a relay we're not changing the power flowing in but we've stopped ground side controlling it we've left the ground circuit open to protect the PCM in an open circuit open heater we really don't have an issue because the circuits open it's not gonna flow any current but in a situation where we would have a shorted sensor maybe two wires melted together or maybe the ground wire shorted to the exhaust manifold or something happened where that sensor was drawing excessive current it could wreck the driver within the PCM so under heater circuit faults it's common to see the driver turned off if you're working with a heater circuit failure you may have to ki cycle the vehicle you may have to clear codes you may have to reset adaptive memory you might have to do a mixture of those things service information will tell you what you have to do but you're gonna have to do something to get that heater reactivated on this one toyota says that it is a key cycle on the next key cycle it'll again check the circuit integrity for the heater if it passes the test that enables the heater circuit if it fails the test disables the heater circuit so it's pretty straightforward but as as somebody working on this car I diagnose the sensor didn't check the heater circuit from the PCM because the sensor was just open so I guess if you wanted to go further you could check and verify that the PCM is able to ground it maybe put a test light in there and like I showed in the last class putting a test light across the heater circuit that'll verify it with a slight load but then it was just replaced the sensor plug it in clear the cold fired up sensor became operational and then both banks went into closed-loop when diagnosing a sensor trouble codes are going to be your first and most accurate way to start look up your trouble codes figure out what's setting the code figure out what is failed to set the code look at freeze frames parameters those kinds of things to determine that and then we got to figure out are we working with a heater issue or signal issue or is it a signal issue caused by a failed heater because again without a heater the sensor doesn't function so again don't expect the the sensor to switch like a like a standard normal o2 sensor and then trim resistors will vary from sensor to sensor so when we come to Asians I didn't cover all of them because this class would just go way too long covered the main ones Toyota Honda Hyundai Kia Subaru and Nissan maybe in the future we'll do mitsubishi mazda at some point but covered the main ones and again there's not a ton of change once you understand the principles of a air fuel ratio sensor so Toyota started using the air fuel ratio sensor in 1997 on the Camry and the Avalon and across the Toyota Lexus line you'll find that they are predominantly running a four-wire air fuel ratio sensor now it's possible that a 1997 Camry and a 2016 Sienna have very different control aspect for that 4-wire sensor it's possible the voltage values might be different but the operation of the sensor will most likely remain the same there might be a little bit more testing with the newer software the newer PCM to do things like slow response or a deteriorated sensor but the operation in the sensor is gonna be very similar to what it was way back in 97 this is a really good line that I pulled directly out of this is a copy and paste out of service information thank you Toyota but the the air fuel ratio sensor is a going to generate voltage that corresponds to actual air I'm not gonna read this whole thing but there's this little asterisk here the air fuel ratio sensor is a current output element so it's generating voltage but it's a current output element therefore the current is converted into voltage so that's where we're getting our voltage the PCM is doing a conversion from current to voltage inside of the ECM measuring the voltage at the connector the air fuel ratio sensor or the ECM will show a constant voltage result this is problematic for testing I'm going to throw the lab scope on this sensor and we're gonna see that signal one in signal two it's roughly like three and 3.3 volts will remain pretty much steady pretty much dead steady at those voltages no matter what I change with the air fuel ratio what's happening is happening inside of the PCM he's just a wiring diagram our heater circuits fed power all the time through a fuse through a relay and then to the heater our heaters going to be pulse width modulated for heater control and then our sensor will have a positive and a negative leg heater resistance on here 1.8 to 3.4 is the actual spec so like I said we're gonna see these sensors come in at 3.3 volts the other one will be about three volts if you're above 3.3 volts the vehicles lean if you're below 3.3 volts the vehicle is rich but again we're not gonna be able to look at that with a lab scope we're gonna be able to look at it with a scan tool but not a lab scope now if our sensor is stuck at 3.8 volts for more than 10 seconds we're going to have a stuck sensors style code where it's gonna be reading rich if it's stuck under two point eight volts we're gonna have a excuse me we're gonna have three point eight is lean two point eight is rich over ten amps will set a heater circuit hi code under point eight amps we'll have a circuit low code and again the heater fault will disable the heater circuit inside of the PCM now this can be a little bit tricky depending on what scan tool you're using if you're looking at generic data in a a lower-end scan tool you might see a voltage that ranges from like half a volt up to a volt these are the air/fuel ratios that you can expect with enhanced scan tool data like we're going to use with our verus today on this car we're gonna see that translated out in the actual voltage that these sensors responding with so just you're gonna notice potentially two different voltage levels depending on what scan tool you're using just know how that correlates basically if it's a lower end scan to and you're getting point six six volts consider that good that is stoichiometric anything lower than point six is going to be a rich mixture anything above point six lean mixture enhance can tool data 3.3 is our cutoff lower than 3.3 riche higher than 3.3 lean all right so here's our wiring diagram for this this Toyota sitting right here and I am currently in Bank two sensor one I have gone ahead and back probed the a to a + and a - a - which is just the bank - sensor one signal circuits I've back probe them both already and we're gonna go ahead and throw the lab scope on them again this is an O six is 250 here you can see a 15 Sienna 3 5 and the same style of setup we're still running an a to a plus a to a - going directly back to the PCM ground what looks like ground side control for our heater element and a shared power source for each sensor to power up that heater circuit so really not any drastic changes in terms of sensor wiring or that kind of thing through what 9 years of production now here's where some of the newer vehicles do have an advantage they have some newer strategy that they're able to determine slow response or delayed response style testing so they're going to look for changes in amplitude or changes in time or delay so what it's doing its watching the current translating that into a voltage and determining what the change rate is from rich to lean or how long it takes for the rich to lean change to happen after it changes the fuel injector pulse so the computers going to force a test during each Drive cycle and parameters are met it's going to directly try to run the engine lean try to run the engine rich and it's going to watch the sensors for either a slow laggy response so it's happening later or a lower amplitude meaning our sensors not as responsive or accurate as it was before so we're seeing that on newer vehicles but again we don't have the ability to see that with the scope we're gonna have to use a scan tool to look at that and it's they give us parameters he at 230 milliseconds after injection control or this voltage but it's not gonna be easy to look at like it would be with a scope so before we get into Honda let's go ahead and throw the lab scope on here and take a look at what we've got yes and Keith has a good point remember to snapshot these slides later for your reference these videos will get posted or this video does get posted directly out to YouTube after it's done so you can go ahead and screenshot the slides later for for reference I don't think I'm missing anything major here and to Keith's point the snipping tool and the PC is great I've talked about this in in earlier classes but I use this program called green shot you just hit your Print Screen button and it opens up this ability to grab a shot and you select what you want and then you have the ability to go ahead and do whatever you want with it I like this because then I can take it at an image editor and I can like I don't know select something and then I can save it as an image or save it in my my paste and my in my clipboard so just something something cool to work with for doing screenshots and that kind of thing so back to the scope we'll get that booted up as that's booting up I'm gonna hook up and I'm gonna I'm gonna show you guys each input and then I'm gonna show you the inputs together I guess let me explain that further I'm gonna hook up channel a to either three point three or three volts I'm not sure which one I'm gonna end up grabbing because I didn't label them but either way channel a is going to be ground side on chassis ground or battery negative or whatever I find under the hood here the other lead is going to be going into one of these signal circuits on our wideband sensor which I have already set some wires out here because the thing is kind of a bear to get to back by the firewall so we're gonna go with a common ground I'm going to go right on top of the engine here and we'll just hook up to this lovely red wire right here which is going to one of my circuits over there channel 2 we're going to go after the other circuit so it'll either be three or three point three whichever the other one wasn't and again the negative lead or the black lead is going to go on common ground we'll just share our ground source from our other one and then we'll go on our other wire here so we're looking at the u-2 sensor signals relative to battery negative or to zero okay now what I'm going to do with channel three is we're gonna look at those signals relative to low reference okay so we're gonna go our Green lead I'm one of the pins which I'm hoping I happened to grab the 3.3 volts on green and then on black on our ground I'm not gonna go to common ground I'm going to go to the other lead or our low reference or our low reference for the signal so that three volts so we should see three to four hundred millivolts or 0.3 point 4 millivolts in between those two signals that's gonna be we're gonna be able to look at that with the scope and it's just a different way to show you what you're scoping the values are going to be the same as long as you reference it properly in your mind okay 3.3 volts is above zero but the actual signal is riding above low reference so our actual signal is like 300 400 millivolts because that 300 are low reference so it just depends on what it is that you're referencing off of now like I talked about the specs before that three and 3.3 those are based off of chassis ground or zero alright those are hooked up hopefully my probes are still stuck into the sensor and let's get the skull poked up we'll take a little bit longer of a time base on here we'll go two seconds per division sounds good again we're working with about 5 volts we're working with 3 ish so we'll go to a 5 volt scale on channel 1 and - and just so we don't mess up our scaling you get confused will grab channel 3 at 5 volts as well so we should expect one around three point three one around three so let's see what we've got now it's kind of cool at kion maybe there we go kion we should see the volts just jump up because the sensor like a normal action sensor we won't see voltage until the sensor becomes operational right we're not going to see that that's switching voltage until the sensors hot and reading exhaust gas a wideband sensor is being fed voltage by the computer at all times so at key on engine off we should see some sort of voltage so just take a look at what we've got here I'll draw in a trace at 3.3 volts on red two point nine volts ish on blue and then green should be the difference between the two roughly 400 millivolts so there we go red is going to be signal high blue signal low green the difference in the two signals and then let's go ahead and we'll fire this thing up an obvious difference in noise that the scope is picking up now that we have a ignition system running let's take a look at our scan tool we'll grab a day to display here maybe all right so we got a data display that's calling out a fo2 so2 sensor data we'll grab a custom graph let's look at bank one sensor one bank two sensor one so if you want your engine to run well you should probably not have the brake booster hose disconnected we'll grab our trims we'll grab that I think that's enough info for us all right so here's our voltages so like I talked about before our voltages right now are based upon 3.3 volts so if it's above 3.3 think of that as our zero mark if it's above 3.3 Raeleen if it's below 3.3 we're rich all right so let's try to get both of them up on the screen here and what I'm gonna do is we're gonna start by forcing this thing lean and we should see it skyrocket but watch the sculpt carefully I'm gonna just reset it so we start back at the beginning there we go all right so we go full lean look at our fuel trims they just went crazy almost stall out the engine but our sensor respondent full lean and our short term fuel trims also responded as full lean just dump and fuel with my other field trim go okay well that's alright so we see a direct reaction but our scope flatlined right and let's do that once more Oh liens [Applause] all right so what I'm gonna do now I'm gonna let the idol stabilize back to normal our short-term should come right back into where they belong and while what I'm gonna do is I'm gonna feed this thing with some propane so I have a propane canister here hooked up to a hose which is hooked up to the vacuum port on the intake manifold where the brake booster goes now we should see our voltage values dip we should see them go under 3.3 as I open this up there we go nice response our fuel trims react almost immediately and I shut it off we should see it go and change almost immediately again a small spike but not much again we'll run it rich almost stalled out the engine close it off so really these field turns are incredibly fast but what I want to show here is we're looking at both sensors at the same time now unfortunately we're not seeing anything on the lab scope at all in fact I'll pause it so we can go back to it but on the scan tool right now we're able to watch and we can even pause this and what we're looking at here is this and this we want him to look roughly the same this is telling us that both banks on a massive vacuum leak or a massive fuel enrichment are showing roughly the same thing if one is showing up way later or one is showing up maybe and that is low of a trace something like that that could show that you have a lazy sensor a sensor that's beginning to fail now it's almost impossible to know exactly what or when the sensor fails that's what we're gonna trust our our trouble codes for if they are gonna be really our true judge and jury and on this thing you know or they're gonna be the one the trouble codes the PCM is what's gonna make the decision on if the sensors failed or not it's failing the test but we're able to kind of watch those sensors and how they react against each other now of course it's only going to work in on an engine that's running to air fuel ratio sensors on each bank and it's only going to work on something that you can create on both banks like if I were to shut a fuel injector off on a single bank the two sensors would respond differently now let's take a quick close look at our lab scope and you'll see very very little of a difference here the only thing that I'm seeing is maybe this line right here so let's go ahead and let's zoom in okay so we definitely went above at this point now on a normal to sensor when we go above 450 we're running rich right now let's start scaling back and let's see if we see that thing dip below the line at any point when we went lean not really any major changes okay so let's call this relatively consistent let's go back a page again here's a little bit of rich let's go back another page see if we can find it where it went the load line there's a little bit below the line but is that enough to call the sensor functional or not I don't know maybe maybe it's functional but you could do some comparative testing again but I think it's much easier to see on a scan tool now it's possible scan tool data could lie to us or give us bad data that's possible but I think it's a lot easier to read on the scan tool than it is on the scope in this case now let's go ahead and look at our other two signals and we see a little bit of wavering on that line but nothing major no major changes off of our our dotted line there which is a big difference compared to looking at the domestic wideband that we were able to manipulate the engine and show that things swing rich and and lean on that sensor it's a huge difference and really on a four wire sensor besides looking at maybe the heater circuit the pulse width modulation of the heater ground I control besides looking at that a lab scope really isn't gonna help us too much okay we can probably honestly just throw a voltmeter on both of the signal circuits the three volt or 2.9 and 3.3 and we should have a pretty good idea that the PCM is sending the voltage that it's supposed to alright you can back probe it make sure that the voltage isn't lost when the car is running something like that you know shake your wiring around run min max on your meter but in this case I don't feel that it's more efficient to run a lab scope to look at a four wire sensor all right you're really splitting hairs at this point on on this line and I just maybe if I was looking at the exact same vehicle running the exact same test or looking at bank-to-bank and forcing just one bank leaner rich I might have a better idea on what it exactly is that I'm looking at but the changes are so small that we just have to be careful that we're not looking at a noise issue a known something with the engine being changed I mean there's really really fine changes in there the scan tool gave the information easier you know a Keith's outta here alright sorry to see you go Keith yeah I agree Keith's right to test this thing with an amp clamp you'd have to have plenty of known good data to look at and that's true I mean I put on the the very low amp the what is it the 30 amp clamp and I wasn't able to pick anything out everything is just very noisy there's a lot of noise in the scope it's possible maybe to pick up amperage in line so you could maybe take like a graphing multimeter or something like that and go in line run the amperage through the tool and you might be able to see an amperage change on there and then that amperage we don't exactly know how that correlates where our footage is a direct correlation according to Toyota Blanc voltage equals blank air fuel ratio if we pull the actual amperage being ran or being used to make those oxygen ions move we're not going to be able to directly correlate that off to an air fuel ratio your son's in Fond du Lac Mike you should should tell them to to pop in we could have a like a little cameo interruption here all right now let's bump into some of the other Asian models of course we only have one that we're covering with the vehicle today but we'll bump into Honda Honda was the first om to use a wideband sensor back in 86 on the Civic and this was the I forget what model it is the high efficiency Civic back in 86 Honda will use a mixture of a four or five wire wideband I just pulled some quick specs out of a 12 accord 2.4 we're looking at that heater coating threshold is eight tenths of an amp to 15 point 2 amps it seems kind of high but our resistance spec on here is 2 to 2.7 for a 2.4 liter Accord and again that falls within our our rule of thumb our rule of thumb on a sensor should be you know roughly that 2 to 4 ohm type of thing and again if you're looking for an exact expect just give us a call but the heater current thresholds to set a code less than 1/10 of the circuit which would be a open circuit most likely or an open heater like this guy right here because when we open the circuit we no longer have a path to ground we no longer have any current flow or 15.2 amps on the high side high current would be a shorted circuit right where now were we're not allowing the PCM to correctly pulse with modulated that ground to get the proper temperature it could be a sensor that's lower resistance under two amps maybe one amp half an amp something like that could be shorted wiring that's rubbed through something like that okay low amperage open circuit type of thing high resistance maybe high amperage would be a shorted circuit again honda has the ability to look at sensor output whether that's a deteriorated spa response which were really looking at the amplitude of the signal or a time differential so depending on how long it takes to go rich or lean so this is right from service information I thought it was kind of kind of interesting so bank 1 sensor 1 output value is 34 or less than 6.8 seconds I really thought that that 34 value was interesting because nowhere did I find in looking at the vehicle looking and doing research no where could I find a definition of what 34 was I think what they're telling us is that is the response characteristic that is the tabled data that honda is using internal of the PCM that we really don't get to output value of 34 or less okay so the PCM again is making our our judgment there I think we can I mean we can trust our trouble close to a point here because they are very accurate in this whole rich to lean switch over time or our amplitude over time it is able to see that very very accurately we could have arranged performance style code basically this is going to be a d-cell type of thing so under D cell with the throttle plate closed we're looking for a predicted characteristics so these sensors looking excuse me the PCM is looking for a proper sensor voltage that's going to be predicted so if it sees rich side or lean side deviation basically what that computer is looking for at that point to get a P to a 0-0 or to a 0-0 3 depending on the bank it's looking for a stuck sensor at that point so driving on the highway you pass by or you get on and on an on ramp you go into D cell throttle plate closes fuel cut enables the sensor is supposed to do something that's known to the PCM there's a characteristic that it understands that at this rpm this load this temperature and probably more factors the oxygen content is supposed to be this if it's reading rich we have a stuck rich sensor if it's reading lean we have a stuck lean sensor or a skewed lean or rich sensor depending on how far it's how far it's gone and depending on what those voltage values actually are that the computers reading Nissan Nissan started using the wide bands back in the year 2000 on the 1.8 liter Sentra again Nissan is using a mixture of the four and five wire sensors a lot of Nissan's you'll find two point two volts to be our zero mark or our stoic mark a higher voltage is going to respond lean a lower voltage is going to respond rich so it's very similar to what our lexus is doing here higher than three point three was leaned lower was rich so on this higher than two oh that's a fire drill or a fire alarm hopefully that shuts off here in a second otherwise we're gonna have to possibly okay I think we're okay that's some excitement so that was fun I think we're safe there's nothing on fire that I can see I have gradual right over there so you don't have to be concerned for my safety if we feel the need to back away we will don't worry I don't need comments in there about not being safe now where was i back on codes you can see that the Nissan's are also looking for deteriorated response the reason why we're doing this the reason why we're looking for deteriorated response is because as a sensor ages it really becomes less accurate and when our sensor is less accurate our fuel control post combustion is less accurate our pulse width modulation of our fuel injectors is then less accurate overall we increase the emissions output of our exhaust system okay when we increase our emissions we are no longer compliant and we have to set a check engine light potentially or we would fail our local emissions test okay so we're looking for deterioration we're looking for sensors that have become slow sluggish lazy over and that'll happen they're in a very tough environment right so they're in hot exhaust gas an initial startup they're being pounded with water from condensation there's a lot of things that these sensors have to be able to put up with and we want to watch them over time because eventually they will need to be replaced they're not going to last the life of the vehicle okay they were never designed to do that they're going to last a certain amount of time most of them I don't know from experience this isn't a spec that I found written anywhere but from experience 100 150 thousand miles seems to kind of be how long they last I have a good idea or I believe that this sensor is original hard to know for sure but it does have the toyota name on the sensor could be original could be bought from the OE doesn't matter it says Toyota on it it came out at 197 thousand on here could be original could be 50,000 miles old really no way to tell but we're watching for that deterioration and making sure that we don't have lazy sensors in our cars lazy sensors is lazy fuel control higher output emissions with Nissan I don't know how many of you run into this but there's a self-learning issue with the four liter in the O 6 Pathfinder Xterra if you do not perform the relearn on this thing you will be putting wideband sensors into that engine continuously until you force this thing to reset it's kind of a weird one you got to turn the ignition on disconnect the mass air flow start the engine let it idle turn it off reconnect the mass air flow check codes clear the codes start the engine and let it idle for 10 minutes kind of an odd procedure why they did it that way I don't know but if you don't follow this procedure on that vehicle you will reset a wideband action sensor related code on here with a perfectly functioning working sensor in that engine so watch for that Subaru 1999 2.2 liter and present and legacy the majority of the sensors you're gonna find on here are for wire but there are a few five wire looking about that 2 ohm resistance mark 4 wire signal you're looking about 2.0 to 2.25 for the voltage and one of the signal wires and then our other signal wires just below that you might end up with a milliamp it on your scan tool if you do zero milliamps is perfect fourteen point seven to one strike if you have a negative milliamps that means this thing is pumping oxygen ions in we're gonna read rich if it's got a positive milliamp Ridge we are pumping oxygen ions out of our exhaust so we are lean we have too much oxygen okay just a couple things I thought this was an interesting service procedure it's usually Keith right that's always talking about check for water well step one of front action sensor has water entered the connector completely remove any water inside I thought this was just a little bit humorous because I've seen a lot of comments from Keith across Facebook and stuff about looking for the water so that's kind of for you Keith it's unfortunate that you've already left I think for the day then we're just checking basic resistance checks of harnesses which I don't know not my favorite type of test and then basically replacing the sensor if it's poor contact with high resistance fix that issue otherwise replace the sensor which doesn't seem like a lot of testing but like we just showed with the four wire sensor we got to look at data because really our lab scopes are not giving us what we need hyundai-kia year 2000 Hyundai ran a wideband in the two liter Elantra majority of them are going to be a five wire sensor on here that heater resistance between two and three ohms roughly two point four two point nine a pretty straightforward wiring diagram you'll find this across most of the vehicles but what I did find was a cool test that I was actually unable to perform with the various I tried on a 12 Elantra to run this exact test so what it's doing is the forced monitor test is going to force this thing lean and rich and look at the response time in conjunction with the rear o2 which is kind of cool so it's doing kind of like an oxygen style looking for capacity type of thing plus its watching for that chain from that front Oh - which is just kind of cool unfortunately I tried to run it with the varus on a 12 Elantra and I was unsuccessful this might be an OE only that's what these screenshots are from is from an OE test if you've had success with that let me know but it's basically just doing a rich lean run like we did with the Lexus pull a vacuum hose that extra air enter in add fuel we're running it rich and lean we're just looking for a response but what's kind of cool is Kia gives you or Hyundai gives you a nice data log from that so we can see these sensor voltage values and then we're able to see the transition time sensor resistance peak to peak voltage so it's it's pretty cool that you're able to see all of this information and then you can save this as a known good and do some comparative testing when you're dealing with these sensors I just note the sensor resistance would be the resistance while the sensor is operational you're not gonna owe mount that resistor excuse me that heater circuit and see seventy-nine and ohms of resistance just doesn't work that way um plausibility check on Hyundai Kia it's gonna look under partial or full load conditions it's gonna watch for that signal if it's above three point one volts it is going to set a fault code for that if it's three point one volts or below it's gonna set a fault code for that I'd also run a fuel cut D cell type of check as well okay so that's a quick rundown on everything is water it's a quick rundown on Asian vehicles pee helped Phelps auto or pee helps Auto you get a good point here with snap throttle snap throttle is kind of a cool test when looking at air fuel ratio I'm gonna probably be able to do it on the BMW we're gonna snap the throttle when the throttle comes back down or closes we're going to go into fuel cut and we should see a nice change in our in our output alright let's just jump into Euro then so BMW started using wide bands on the 7:45 back in o2 majority if not all of the sensors they're using are going to be a 5 wire sensor just know which system it is that you're working with which DME which software which manufacturer of the system was because they will operate different they'll give you different codes depending on if they're Debashish of the Siemens system short battery voltage for sensor will indicate a rich condition where on the Siemens system it indicates a lean condition ok just know which system it is that you're working on so that you aren't chasing your tail when it comes to specs and testing the heater circuit low and high codes parameters are 10 milliamps on the low end and 11 amps on the high end so open and shorted 10 10 millionths - 11 amps here's the diagram that we're looking at again we're working with a 3 litre straight-six motor so BMWs kind of cool that they separate that straight six into two banks we're gonna be probing into the sensor that's reading the rear bank on here and we'll go over there in just a second BMWs also watching the switching rate and the amplitude it's going to force artificial lamda modulation sounds super fancy but all they're doing is forcing the vehicle rich or lean and watching the time it takes to switch and the amplitude or the values that it's able to obtain that's all it's doing is it's forcing a test to run okay kind of cool little screenshot here for you guys that just has a lot of the codes related along with threshold values so this is what we're really looking at is how long did it take to set and at what values did it set okay and I think we'll just run through Volkswagen Audion Mar Sadie's really quick just because we can and then we'll jump over to the Beamer 99 on the 1/8 and 2 beedo golf and Jetta mainly again using a five wire sensor heater resistance two-and-a-half to 10 ohms seems seems a little odd to me on that 10 ohms seems a little high but that was the spec that I was able to find i haven't found an actual sensor that reads at that yet though not a lot of information on Volkswagen Rd they're really doing what everybody else is doing using a 5 wire sensor doing the same type of tests I think if we had a more European enhanced scan tool we might have a better shot at looking at more data with these vehicles you'll see with the BMW using the various I really have very limited information actually we're gonna be using the autel on there but the data was roughly the same very limited information so you might get more when you're looking at this with a factory tool or something that's more European based but we're gonna look at these sensors today as a not a non euro shop Mercedes Benz all three is when they started using them on the 1.8 liter and the C 230 again five wire sensors it is capable of interpreting 0.7 lamda to 4.0 lambda that lamda pid' 1 lambda is stoichiometric under once 0.7 would be considered rich anything under 1.0 is rich anything over 1.0 is lean so just keep that in mind if you have a lambda pit and on their fuel ratio pit on your scan tool under one rich over one lean okay all right that is it for that I think we're going to bump over now onto our BMW and try to get everything moved without disconnecting everything okay I just gotta grab the lab scope I'm gonna look at a couple different things what's really nice with this BMW here is the sensor connections are right up on top of the valve cover so everybody's always I don't know complaining about working on BMWs but or European in general but honestly this was kind of nice to be able to access the connector right there instead of having to shove my hand between the cylinder head and the firewall on this and this little Lexus over here that was a lot more of a pain to get that one hooked up alright so what we're gonna look at on here is gonna be a good way for you to be able to test or watch this sensor operate maybe if you don't have a scan tool it's probably unlikely that you have a lab scope and not a scan tool but if you forgot your scan tool at home or you want to verify that the data that you're actually getting is accurate or you just really like using your scope and you want to get it out of the box because you haven't used it for a few days you know whatever but we'll be able to show some direct manipulation of the air fuel ratio and show you how it responds with the vehicle so I got three channels active I think what we're going to start with is but we're gonna start with taking a look at the heater just to show you guys how the pulse width modulation operates as the sensor begins heating up and then how it changes as the sensor warms up gets up to operating temples for the moment just run channel a run actually will run channel B as well we'll grab power and ground so we're gonna run them at 0 to 20 and we're at two seconds per division so I'm gonna run channel a grab an alligator clip here we're gonna run our black lead ground lead on a chassis ground or battery ground so we're gonna reference off of zero on here and then I forgot my probes and then we're gonna run our other lead here we'll run channel a into one of the heater circuits which is pins three and four on this one which is the middle of the connector so back probe into that one that should give us something voltage or ground and then channel two will reference off of that that zero point that better negative and we'll go into the other the other side of the heater and we'll see what we've got okay get this thing fired up and take a look [Music] [Applause] all right so channel a is our ground side control pulse width modulated and channel B our red channel is our voltage pit so you can already see our pulse width is changing as this sensor is heating up so here our signal was wider keeping our speed around longer and now it's narrowing so I'm gonna let it run for just a second it's kind of normalized now by the looks of it and what you're able to do with this is you're able to watch both sensors if you wanted and compare the heater time between the two so maybe you have an intermittent issue or you think a sensor might be going bad something like that you're able to compare the time that it takes to heat up because here in the beginning we have a long pulse width modulation and then we bring it over we'll start to change that all right as we continue to come over you'll see more time where that blue trace is up here at 12 volts that means we're not grounding the circuit at that point we're not flowing amperage oh I gotta throw the hose on it the alarm is going off at least it's not as bad as the fire alarm was all right so we'll continue over and you can watch as our our time spent up here is increasing the more time we have spent at that battery voltage mark the less current we're applying to the sensor is basically what that is we're not grounding the sensor inside the PCM we're not allowing that path for current to flow through the sensor so we are basically creating an open circuit there right so when we're up at battery voltage the voltage is running through currents running through the sensor and then it's piling up at the open circuit mark and that's inside of the PCM so we go open circuit we spend more time up at that up at that battery voltage line meaning our heaters is drawing less current on that sensor all right so that's heater current now we're gonna take and let's grab pins 2 and pin 6 are going to be our nerd cell and I'm gonna actually go directly across the two so I'm going to take channel a and our ground set those down and I'm gonna go directly across so one is going to be on pin 2 the other one on pin six and this is going to give us what that nerd cell is reading it should be roughly that 450 millivolt mark thank you and six there we go we'll drop off of the 20 volt mark will come down to a volt and I do have the polarity switched around let me uh I'll just reverse the polarity on here and we'll see that come up above zero all I'm doing is switching the blue one and black the positive and negative and there we go we'll actually put this right at the 450 mark all right so now our line is at 450 millivolts so this is the cell that's being maintained by the pumping cell the pumping cells job is to pump those ions in or out to keep this at 450 millivolts so we'll see a little bit of change a little bit of wiggle in this line but we're not going to see what we're gonna see on the pumping circuit and so we're gonna look at next so on channel 2 what I'm gonna grab is another back probe grab the whole box that'll work we have another table so on channel 2 we're gonna grab one of the pumping pins we're gonna grab probably will start off with pin 1 pin 1 is going to be our pumping circuit that is not going through the trim resistor pin 5 is going to be our trim resistor pumping circuit so we're going to show them both just to show you the difference somewhere in my alligator clip we're gonna reference this to battery negative 2 chassis ground so we should see a voltage on here anyone make sure if I pull this in there and good enough alright so we should already see some change in this line as the vehicle manipulates itself at idle and then we'll grab one more and we'll go in pin 5 again we're referencing off of 0 I think we got to turn that channel on drop our voltage down here a bit too far so you can see red and green are laying directly on top of each other and they're gonna maintain themselves pretty close on that line now let's get the scan tool operational and let's look at some data on there so I'm going into action sensor control we have additive and multiplicative field trims additive is going to be are basically at idle off load multiplicative is going to be our loaded trims oxygen sensor control that is meaning that our sensors are active signal upstream is really what we care about so we'll grab that we'll grab that and let's just grab some trims and we'll see we got so I'm gonna go ahead and I'm gonna graph these so it looks like 1.5 ish is our mark on here for stoic we run them both like that and now we're gonna start doing some manipulation all right so I've gone ahead and under the hood here let me grab my flashlight but if we get a close-up you'll see the purge solenoid right there right there's the purge I've gone ahead and I've got the hose ready to disconnect so we're gonna force this thing lean and then we're gonna force it rich with that propane so let's try to get both the scan tool and the lab scope up on the screen so you guys can see how exactly it is that the system is going to react when we when we manipulate it so we'll start by going lean I'm gonna go ahead and zoom in my channels here oops okay so that's lien and you can see our scan tool has gone full full lien it's increased voltage just like our Toyota did and now I'm gonna kind of plug it up a little bit that should return it back to normal ish and sell the dip on the lab scope right now I'm gonna force it rich open up some propane here and there we go we're starting to bring it into the rich side I'm gonna shut it off and our scan tool should respond and our lab scope responds it goes lean because it's got a change the the fuel trims are going to be a little slow to respond on here they don't seem to respond as fast as what the Lexus did again we'll open up some propane she dips rich just like we want to see shut it off and we lost our ground put that bag on ignore that glitch Wow it's gonna go to a different ground spot I guess there we go all right and I'm gonna pull this out we'll go lean barely running and we'll put it back to normal so what we would really end up wanting to do here is grabbing bank 1 and bank 2 because that would give us a good comparison between the two so instead of looking at both pumping circuits I'm gonna grab pin 1 on both connectors and take a look at what we've got from both sensors and they should be if I can keep my ground on should've grabbed a different different clip try that again so bank 1 in bank 2 on this straight-6 engine should respond pretty similarly I would expect maybe a little bit of a change I'm gonna move our nerd cell down here just so it's out of the way you can see a little bit of discrepancy between the two banks let's go ahead and pull that vacuum hose again there we go both banks go lean plug it back in both thanks go rich and then they say stabilizer or find themselves at a happy spot now if we pause this and go back one page you'll see a slight dip in our nerd cell right here where we went and changed that little bit of a dip is this sensor doing this job it's this sensor working so again a slight change but nothing nothing major not not like looking at you know not like looking at this change here no this is an obvious obvious change at both bank 1 and bank 2 are doing I am a huge fan of comparative testing so if we're doing something on here where we're dealing with a sensor issue a sensor failure sensor fault whatever if we're looking for a slow sensor or a leggy sense or something like that compare the banks if you have the ability compare the banks it gives you so much vital testing information and what are the chances of both sensors failing at the same time if both sensors are doing the exact same thing find something that's changing the air/fuel ratio for the entire engine maybe a vacuum leak or maybe an issue with that if you have a single bank issue a single sensor issue it's more likely to have a sensor failure or a single Bank issue maybe an ejector issue or a coil issue a vacuum leak issue on a single Bank okay use comparative testing to your advantage in a properly running engine bank one and bank two should run very very very similarly and as we saw when we manipulated this engine they both dip rich they both go lean at roughly the same scale so use that to your advantage when you're diagnosing this thing it's way better than having to pull in a known good with a three litre straight-six in there and running the test again having to hook all that up again use what you have available and a lot of times we can compare sensor to sensor and get a lot of information alright I think let's bump back over to the other table questions on that so again if we go back to here in the diagram we were looking at first the heater circuit so we were probed on pin four and three looking at our heater circuit ground side pulse width modulated control here power fed in all the times through 30 amp fuse then I think it was two and six I think we were probed into right two and six were our nerd cell I have to write myself notes because remembering this live can be tricky but two and six are nerd so one in five are pumping circuit okay so one through the trim resistor the other one is not but those are what you're going to use one in five pumping two and six for trim or nerd self excuse me nerd cell not true and so I learned so and three and four for the heater thanks for a $2 donation for putting up with you guys in chat I love the chat so I will put up with you guys always cuz it's just fun unless somebody's being mean let's see here somebody being mean back here I'll have to read back through it later alright any questions on this it's all in good humor of course and that's that's what I have come to expect from you guys a little bit of razzing of me is is always fun thank you I think that's Brian right for the donation I appreciate it the alarm we have a carbon monoxide monitor in here basically when the alarm is beeping there is a high level of carbon monoxide so the exhaust fan will probably eventually kick in and basically making sure that I don't pass out on camera it should be good any other questions again this was just a good I think overview on looking at the the Toyota or the the Asian really aspect a lot of Asians will run for wire sensors and then the Europeans a lot of them will run a five wire sensor and really guys all we're looking for on a fiber sensor get access to that pumping cell and take a look if you can see some voltage out of there most of the time you will now depending on what you reference to again with that ground lead on your scope depending on what's your reference to will change your voltage values but as with just about every bit of testing that we do as people diagnosing cars we need to be looking up our information right use your service information if you have access to factory information or the different repair resources like we use go ahead and look for specs in there lookup code set criteria look at what it's taken to set that code so you can get some values out of there so you can apply that to your testing because there's really no sense in performing a test unless we know what we're testing for each vehicle each manufacturer each model each engine could have different testing parameters it's impossible for me to cover everything in regards to Ural and Asian but this was intended to be an overview to look at the different sensors and to really have you not not scared of working on the Euro cars a lot of people turn euro cars away as long as you have a little bit of time to do some research and understanding of the system they really don't operate different than anything else it sometimes this stuff's harder to work on I'll agree with that but on this wideband sensor it doesn't get easier than slapping both of the connectors right up on top of the valve cover for our testing I mean way easier than a lot of the cars that we work on so any mmm Oh two cents are affecting a cat code to appeal 420 cat code I Keith loves put me on the spot but I believe when we're doing a 420 test we're going to compare we'll do some comparison between front and rear we're gonna do some intentionally running Ridge some intentionally running lien to look at oxygen storage capacity yeah so a 420 code I mean we pretty much already know 420 code is gonna probably end up needing a cat unless you can prove out that the o2 sensor is sluggish or not responding to the proper amplitude but the PCM is gonna look for certain values on that sensor okay I think that's probably about it guys I hope you enjoyed this class know I didn't just say that okay let me rephrase we're not putting in a catalytic converter for appeal 420 code we're doing our proper testing cuz that's always always always always best cuz you know really a lot of times a 420 code can set for the dumbest reason like a small pinhole leak or a bad flex pipe something where there's excessive oxygen getting in there you know something like that could cause it so again can you guys head out to here and check out our tech portal that's how I'm gonna be able to get your email addresses right now to send you guys updates so create an account put your email in you'll get added to the list so that you'll be able to get a email update usually I send them a week or two before the class they're usually always coming in on Thursdays but that way I can advise you to when the next class is which is looking to be September 5th unless something changes but again that's where that email comes in so if you sign up for this I'll put you on the mailing list and you'll get an e-mailed reminder about the next class so I think that covers it look at your service information for wideband sensors air fuel ratio sensors so you have a good understanding of what it is that you're looking at read your code set criteria it's really really gonna help when you're diagnosing these cars scan tools and lab scopes go a long way in here there's no way our volt meter would have been fast enough to track those changes in that air fuel ratio okay it's gonna give us skewed data graphing multimeter might be able to do it lab scope is going to be ideal all right thank you so much everybody for coming watching from all over the world today everybody was announcing where they're from I really appreciate that you know making it fit into your schedules it's I know it's hard to fit in a a live class in the middle of the day and I'm almost leaving before the t-shirt giveaway whoo that would have been bad Congrats to the five people who want it last month today here is the question two technicians are discussing proper operation of a wideband air/fuel ratio sensor tech a says that the sensor signal reading under 1 lambda during DSL is normal is that normal for the sensor to read under 1 lambda during decel Tech B says that a lower air fuel ratio signal amplitude can be caused by both sensor deterioration or potential rich and lean conditions what's going to affect the amplitude signal on our air fuel ratio sensor give me an answer tech a tech B both or neither and then give me a reason why explain it let's see what you guys think giveaway is only good for today 8 8 19 August a at the 19 and email it out to NC Becker at NGK spark plugs calm first five people to get the correct answer that haven't previously won a shirt will win a awesome diagnose before you try Ignace t-shirt okay again congrats to the winners from last than all of our previous winners and we'll throw the question up once more with my email address send that out today and again first five people to get the correct answer around here will be a winner all right so I think we're gonna close it out if you haven't already please give us that thumbs up if you enjoyed this today put your comments below questions below I'd be happy to get back to to any of your questions that I might have missed or given more in-depth explanation on something whatever you're looking for go ahead put those comments below share the video if you'd like with your friends and stuff like that and yeah I guess we'll see you in September not sure we're gonna be covering them but I'm sure it's gonna be something fun so we'll see you in September thank you for coming and we'll see you guys next time happy wrenching everyone thank you you

Channel: GoTech

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Id: 9YrAlN6cgN8

Length: 89min 16sec (5356 seconds)

Published: Thu Aug 08 2019