DODGE RAM 1500 CRANKS BUT WON'T START DIAGNOSIS & FIX

[Music] hey guys what's up it's eric with advanced love automotive welcome back to the channel welcome back to another quick case study uh today i got called out to come take a look at this 2012 dodge ram 1500 it's got the v6 3.7 liter engine and the customer complaint is that the vehicle is a crank but no start what she's telling me is that she was driving somebody pulled out in front of her she had to slam on the brakes after that it seemed like the truck really didn't want to accelerate she would put the pedal to the floor but i just didn't want to get out of the way so she had it towed back to her apartment we're here to take a look at it you guys know how we do it let's go ahead and get started all right guys so first things first i'm going to go ahead and verify the complaint so we're going to hop in to the vehicle here i'm going to stick the key into the ignition crank it and see if this thing starts key in the ignition turn the key on now one of the first things before i like to start up is make sure to see if we have a check engine light and we do you guys can see we do have a check engine light the other thing that we're going to look for when i crank the engine over is we're going to look to see if the tachometer needle jumps that's going to give us an indication whether or not we have a crank signal so let's go ahead and crank this thing over all right so you guys can see we have a nice healthy strong crank the battery seems to be fully charged and again if you guys took a look at the tachometer you could see that we actually did have some movement showing us that we do have a crank sensor signal and like i said we do have the check engine light that lets us know that the engine computer is alive and awake the other thing that i noticed is that while it was cranking if you listen to the way the engine cranks the rhythm the cadence of it it sounded pretty healthy it didn't sound like we have any kind of timing issue or compression issue it had a very even rhythm to the way this thing cranks so i don't believe that we have any mechanical issues so the next thing we could try to do is maybe hook up a scan tool see if we have any codes and maybe we can get some direction that way all right guys so i've got the scan tool connected we are using the think tool today i'm going to go ahead and click on pcm powertrain control module we're going to read fault codes we're going to see if we can get any direction as to where to go next so here we have three fault codes stored the first one we have a po218 transmission high temperature operation activated i believe that means that maybe at some point in time the transmission temperature may have gotten too high so i don't know if that has anything to do with our no star condition it's very highly unlikely i don't think that that code is related but let's move on to the next one we have a u1418 implausible right wheel distance signal received so this i believe has to do with maybe a wheel speed sensor again i don't believe that that's going to cause our crank no start condition and then last but not least we have this p1797 manual shift overheat so again i believe that this code may be related to the first code which is our transmission going over temperature which i mean could have something to do with what we're dealing with but i really don't think so it's highly unlikely to me there is no reason that these codes in the transmission should cause this engine to not want to start so i think the next thing that we should do is probably do some basic checks you know when we have a crank no start condition you really want to start by keeping it simple do some basic checks in this case we could check for spark we could check for fuel supply we could check for injector pulse we can check for air make sure we don't have a blockage in the air intake or something like that some very simple basic checks so i'm gonna go ahead and put the scan tool away we're gonna move under the hood and see what we can find out all right guys moving under the hood let me show you the first check that i'm going to do if you look right over here we have the ignition coil and what i'm going to do is i'm going to check for spark by disconnecting this spark plug cable right here and then i'm going to take my test light here that i have connected to the battery negative and what i'm going to do is i'm going to put it near the coil here and i'm going to watch for a spark to jump across the gap between my test light and the ignition coil now it's important to note that i'm not looking for the test light to light in this case i'm just giving this spark coming out of this coil a path to ground through my test light this is the fuse box right here also known as the tipping module so we're going to pop this thing open and then we're going to locate the starter fuse and if you look on the lid here we have a little legend and a diagram that tells us what each fuse and relay is for so let's take a look here all right so if you take a look at k3 it tells us here starter solenoid relay and if we look at the layout here k3 is going to be i believe this one here if i'm not mistaken it's kind of hard to read but if you look here that looks like it says k3 so if we take a look at our relays here that's going to be this middle one right here so let me get a jumper for this and we'll see if we can crank the engine over alright guys so over here i have my relay tester and jumper kit and in the kit we have this little uh switch relays that you kind of just put in place of a relay and it allows you to jump it's got this little rocker switch at the top of it and so this is the relay that i pulled out of the fuse box right here and so this relay is a match for this so we're going to just stick it in place here like so and then now if we flick the switch on we should be able to crank the engine over let me close this kit right here and by the way if you guys are looking for a kit like this it's made by lyle tools i'll put a link in the description very awesome must-have tool for any diagnostic mechanic or technician and so i'm going to go ahead and flick the switch right here and pay attention to the engine we'll see if it cranks okay the engine cranks over so let's go ahead and get our test light and see if we have any spark all right so i'm gonna go ahead and crank the engine over and again we're going to watch for uh spark to jump across the gap here on the tip of the test light uh by the way the ignition isn't on position so we need to make sure that we do have the ignition on so let's go ahead and get this close to the coil here i'm going to crank it over and let's see if we have any spark all right guys so let me apologize unfortunately i don't think that that's going to show up on the camera now i can tell you right now we definitely have spark because i can hear it i can barely see it you know for one thing if you take a look at the uh um the little nose that's sticking out here it's kind of deep in there so you know i really have to stick the test light into there so it jumping this gap here is already a good i don't know maybe inch and a half or so and i don't think i was able to catch it on camera but i can tell you right now i could definitely hear it and if i looked at it from the side inside of there i could actually see the spark now i will say that it was pretty weak i don't know if that had anything to do with the battery getting low because at a certain point the battery did get too low i had to put my jump pack on there but to be honest my jump pack is not fully charged at the moment so i feel pretty confident that this thing does have spark now the other thing i will say is that uh this system seems to be some type of waste spark ignition system because it is actually only three coils for all six cylinders so if you take a look uh this coil is a direct ignition coil that goes down into the spark plug there and then there's a wire that comes off of here going to the other side of the engine so it seems to me like this coil supplies a spark for two spark plugs so i mean that may or may not have anything to do with the fact that you know i don't see a very strong spark coming out of this side of the ignition coil but like i said i'm pretty confident that we do have spark now the next thing i wanted to check was for fuel pressure unfortunately the problem that i have right now is that i didn't bring my quick disconnect tool to disconnect the fuel line right here because i actually brought my fuel gauge to check the fuel pressure but i just i didn't bring the little quick connect tool with me so i'm going to have to resort to doing some very rudimentary checks to see whether or not the fuel pump is coming on uh for one we could do a test where we just listen for the fuel pump to see if it comes on again we have the scan tool here so the nice thing about the scan tool is we should be able to actuate uh the fuel pump to come on let me go back into this it's right there fuel pump relay control state we'll click on that now if you take a look at the menu down here in the active test you can see that we have a couple different ways we can turn the fuel pump on for one we can just hit the on button and that will turn on the fuel pump continuously by turning the relay on then we can flick off to turn it off if you look here we have this toggle button what that's going to do is when we hit the toggle button the scan tool is going to toggle the fuel pump on and off and on and off until we shut it off so what i'm going to do is i'm going to go ahead and hit the toggle button and let this thing toggle the fuel pump on i actually heard something click in the relay box over here you guys can see it's set to toggle so if you pay attention you can actually hear the relay clicking there you go listen you guys hear that on off on off so the relay is flicking on and off now one of the first things we could probably try to do is maybe feel the fuel line you know sometimes when the pump comes on you can feel vibrations in the line which i don't feel any vibrations here man i really wish i could disconnect this fuel line i just didn't bring any disconnect tools with me yeah like i said i don't feel any vibrations coming through this fuel line here i can definitely hear the relay clicking on and off i'm just going to feel around to see which relay is the fuel pump relay because while it's clicking on and off i should be able to feel which relay is clicking on and off [Music] huh well that's funny i don't feel any of these relays clicking but i can definitely hear it clicking i wonder if it's clicking from inside the box yeah maybe this fuel pump relay is actually built into the tipa module if we take a look at the legend here let me see if we have any relays that say fuel pump relay so if we look at the k's those are going to be all of our relays k1 we have run accessory relay k2 is run relay k3 starter relay k4 is run start relay five is pcm six is ebl relay uh seven is hvac nine is hvac 10 is asd and eleven is radiator fan low relay yeah so actually i don't believe that there's a physical uh relay on the outside that we can replace for the fuel pump relay i actually think that the relay might be built inside let me see if i can pull up a wiring diagram and check it out all right yeah guys so take a look at the wiring diagram here hopefully you can see it if you look at this uh dotted line here this box that's going to be our fuse box or our tipa module and if you look at the other dotted line inside of the tip the module that's going to be the brain to the computer inside of the tpm if you look right over here this little square that's our fuel pump relay now if you pay attention it's drawn up like a normal four pin fuel pump relay what you'll notice is the control for the relay is actually controlled by the circuit board inside of the tipping module that means that the tip of module has full control of the fuel pump relay now if you take a look at the fuel pump relay itself you'll see on the switching side or the output side the power actually comes out through this fuse m25 which is a 20 amp fuse and that power comes out on this dark blue and orange wire which if we follow it down goes over to the next page as number one okay so on the next page here is our number one right here our dark blue and orange wire and if you follow it up you can see it goes straight to the fuel pump module and then when the power goes through the fuel pump it comes out on the other side here directly to a body ground or excuse me a ground on the frame rail now that's interesting because one of the things that i did have in the back of my mind is whether or not this vehicle was equipped with some type of fuel cutoff device much like in the fords where a lot of times you'll hit a pothole that'll flip the inertia switch which causes the fuel pump to shut off and all you have to do to get it to start is to push the button on the inertia switch but looking at this wiring diagram it doesn't seem like there's anything really between the fuse box and the fuel pump module itself this fuel pump relay basically just gets grounded by the tip of module the power gets sent out on this dark blue and orange wire but it has to go through the fuse m25 first so it doesn't look to me like there's any safety provisions on this end of the circuit now what we could try to do next is maybe move back over to the vehicle locate this m25 fuse and see if whenever we toggle the switch on we have power coming to this fuse because like i said i think this fuel pump relay is actually built into the tipa module now just so you guys don't get confused tipum stands for totally integrated power module which is also known as the fuse box so anyways let's move back over to the vehicle and do some quick checks okay guys so i've gone ahead and located the fuse this is the 20 amp fuse right here m25 that is our fuel pump fuse so whenever the relay clicks on we should have power on this fuse now before we actually check that fuse i do want to do one more basic check and again we're going to listen for the fuel pump so i'm going to hit the toggle switch to toggle this fuel pump on and off and again i can hear the relay clicking whenever i toggle this on but like i said i don't feel any vibrations in the fuel line and the other thing is that we should be able to hear the pump coming on where the fuel tank is at so if we move back over here you can see where the fuel tank is at now if we listen closely i don't hear the fuel pump coming on usually when the fuel pump comes on you'll hear like a whizzing or buzzing noise but if i listen very intently i don't hear anything now the other thing is we could probably take the gas cap off and put our ear to the filler neck and listen for it yeah i don't hear anything coming on so it doesn't sound like the fuel pump is coming on to me the next thing we could do like i said is go back and double check our fuse so let's move back under the hood okay so moving back under the hood again the scan tool is set to toggle so it's going to be toggling the relay on and off i can hear it clicking what i'm going to do is i'm going to touch the fuse and we're going to see if we have power you guys can see right now we do have power it clicked on it toggled it off it toggled it on toggling it off on off on so we definitely know that the relay is working the tip of module is turning the fuel pump on uh but let's double check on the other side of the fuse because it's possible this fuse could be blown so we're only checking it on one side so let's check the other side you guys can see off on off on off on so it looks like that fuse is good i think at this point we really should be concerned about the fuel pump all right guys let me show you what my next check is going to be what i went ahead and i did is i pulled out our 20 amp fuse for the fuel pump and if you look right here i have this little fuse buddy jumper and what that's going to allow us to do is take that 20 amp fuse stick it into here and it's going to give us this wire loop here that we can actually clamp an amp clamp over it so we're going to stick this back in there with our 20 amp fuse and then i'm going to take my amp clamp here of course we're going to zero it out before we clip it on there i'm going to open up the jaws here and i'm going to stick it on to our little fuse buddy and this is going to allow us to check the current of the fuel pump so if our fuel pump is coming on we should see somewhere around 8 amps of current so if you take a look at the meter here i'm on a lab scope and we're at a 10 amp scale right here so i'm gonna go ahead and toggle the fuel pump on you guys can see the fuel pump is on i heard it click if we take a look here pay attention we don't have anything here so i'm gonna turn the trigger off see if that changes anything turn the trigger off uh nope we don't have any amperage here let me hit our zero button pay attention you guys can see when i hit the zero button it did spike a little bit so we know that this is working let me flip it around so there's our am clamp but as you guys can see we don't have any amperage going on here so it doesn't look like the fuel pump is turning on at all that really aligns with my suspicion here that we may have a problem with the fuel pump or fuel pump connection so i think the next thing we need to do is maybe get up under the vehicle check the fuel pump ground and then check the fuel pump power all right guys so the first thing i want to show you is if we move up underneath the vehicle here i've actually located the fuel pump ground if you take a look on the frame here you can see that our ground is located right there i'm going to zoom in a little bit there we have it that is our fuel pump brown to the frame and if you take a look at it i mean i don't see any corrosion or anything and when i move it it's not loose if i take a look at the wiring none of it is cut we don't have any damage to the wiring here i've already done a full visual inspection across the wiring harness and i haven't seen anything obvious here so this ground looks pretty good that means that the next thing we need to do is we need to go to the connector at the top of the fuel tank and check it directly at the fuel pump all right guys so this is not going to be exactly easy but if you take a look this is our frame here and if we move up through this hole in the frame we can actually get a good visual of our fuel pump and the fuel pump connector so if you take a look at the connector right there you can see that it is fully connected now i did stick my hand up in there grab it tug on it and uh it is well connected and again if you take a look at the wiring harness we don't see any obvious signs of trauma or damage it doesn't look like any rodents have been up here so i definitely think the next thing that we should try to do is back probe the connector check our power and check our ground okay so just to show you on the wiring diagram what we're going to be checking again this is the fuel pump module right here we're going to be checking two wires the first one is going to be pin number one which is this black and gray wire that's going to be our ground so we're going to load check our ground and then the next one we're going to be checking is pin number four which is a dark blue and orange wire that's going to be our power feed coming from the fuel pump relay and the fuel pump fuse i'll put a picture up on the screen right now so you guys can see the two wires pin number one and pin number four they're on opposite sides of the connector so i'm gonna go ahead and move on to the back of the vehicle back probe those pins and we'll see what we got okay guys so we're underneath the vehicle you can see the scan tool i've got it set up so that we can turn on and off the fuel pump i've got my power probe here connected to the lead and if you follow the lead up here you can see that i have it connected and back probed to our power wire on the connector there now if you guys have ever heard the phrase easier said than done that was definitely easier said than done so we're going to be checking for power to begin with i'm going to go ahead and toggle this fuel pump on i'm gonna hit the on button and we're going to watch for the power probe we're gonna see if we have power on that circuit so pay attention here okay so i don't see any power let me make sure i have a good connection there stick my arm up in there damn it oh yeah i didn't have it all the way in there we go all right guys as you can see i didn't have the back probe all the way into the connector but once i got it in there you can see that we have full battery voltage and uh i mean our battery is a little bit low but we do have full battery voltage i'm gonna go ahead and toggle this thing off you guys can see that when i toggle this off this is going to turn off and there we have it it's off and then toggle it back on hit the on button wait for this thing to say on there we have it it's on and take a look at the power probe you can see that we have full battery voltage so we know that everything from the fuse box the tip of module all the way up in front of the vehicle the wiring all the way back to the fuel pump directly at the fuel pump is good so now we need to check our ground all right guys so this was even more difficult to get to but i was able to do it i am back probed on the ground wire once again let me take you guys up here take a look at the connector you can see that i have back probe on our black wire which is our ground if you follow this down once again i have it connected to my power probe and you can see right now we do show a good ground now i know some of you guys are not going to think this is enough because we're not load testing the ground so what i'm going to be doing is hooking up my little test light bulb this is basically a 9006 or 9007 headlight bulb and i've got some wires coming off of it so this is how we're going to load test the ground let me set this up alright guys so we have our headlight bulb connected basically just like a test light and if you take a look at it we have just two wires coming off of it so we're going to feed a power through this test light and as long as we have a good ground we should be able to light this test light nice and bright so if you take a look one of these wires is going down to my power probe where i'm going to flick this rocker switch to power and that's going to send power through this wire through the light bulb and it's going to come out on the other side and it's going to go through this green wire which is connected to our ground at the fuel pump so if we have a good ground we know we have a good power because this is connected directly to the battery but as long as we have a good ground this light bulb should light up nice and bright now the other thing i do want to mention is that i did go ahead and pull the fuse out of the fuse box for the fuel pump because we don't want to backfeed power into the fuel pump power feed because we still have the connector connected so i'm going to go ahead and flick the rocker switch on pay attention to this light bulb we'll see what happens all right as you guys can see our light bulb is lit nice and brightly i'm gonna let it off back on off on off on so that is proof that we have a good ground at this point we're pretty much confident that this thing is going to need a new fuel pump tomorrow all right guys so it is the following day i'm back i'm installing the new fuel pump i already got the gas tank out let me show you what it looks like all right so over here on the ground we have the fuel tank out of the vehicle wasn't too difficult to remove just had two straps holding it on all we had to do was disconnect a few lines at the top and disconnect the electrical connector at the top of the pump one thing you don't want to forget is that over here there is an evap valve the esim and there's a connector on that you want to make sure you disconnect that before you try to drop the gas tank because you could potentially damage that if you forget to disconnect it anyway i went ahead and i cleaned up the top of the tank here before i actually removed the pump now one of the things i did notice is that when i pulled the pump out it was actually just hanging in there these rods that hold the module assembly to the top of the pump here had actually fallen out and so i had to fish these out of the bottom of the gas tank using a magnet so you can see the spring and the rods um well actually i wonder if there's still another spring in there did i miss one because maybe there's a spring on each side let me stick the magnet back in there and try to fish it out all right so i just have this magnet extended into the fuel tank and i'm just kind of running it along the bottom of the fuel tank seeing if i can catch anything um but nope it doesn't look like there's a second spring i guess i was just assuming that each rod had its own spring but i guess it's only one spring anyway we can probably compare the new pump to the old pump if that's the case because like i said there's two rods in one spring but over here we have our new fuel pump now i will say that this fuel pump was not cheap my cost wholesale was about 450 dollars so you know i feel bad for you guys who have to replace the fuel pump on your dodge chrysler product and you have to spend 500 on a fuel pump so anyway let me open this thing up pull the pump out and we'll take a look at it all right so taking a look at the new fuel pump you can see uh it's pretty much the same as the other one but here we have our two steel rods and i guess the springs actually go into the module assembly on each of these rods yeah because it does feel like this thing is kind of spring-loaded so i'm curious where the other spring went um i wonder if maybe the casing on the other one had cracked maybe it's possible that uh she might have hit something or something on the road hit the bottom of the fuel tank pretty hard and caused this thing to crack let me take a look at the other fuel pump and we'll compare this kind of top part of the module here let me take a look yeah so taking a closer look at the new pump versus the old pump it seems like there's a whole plastic piece around the top of the fuel pump module that's missing if you take a look you can see that all this top part of the plastic is covered and this one is missing that whole plastic cover and the other thing that i noticed is that if you take a look at this connector here now i don't know if this disconnected because when i lift it up on this this is how i pulled it out of the fuel tank but this connector right here with the red and black wire is actually the connector for the fuel pump itself so if you look right down in here you can see the fuel pump there's two pins right there and uh this is the connector so man i wonder if this fuel pump was just disconnected inside of the fuel tank you know maybe she had hit something or something hit the gas tank enough for it to jolt the piece of plastic to come off of the top of this fuel pump module these rods came out and the spring came out and then eventually it bouncing around the fuel pump just came unplugged so i mean that's kind of my theory but the other question is if that's the case where is that plastic piece because i don't see it in the fuel tank i don't want to drop my phone in here but i do want to try to get a good look inside of the fuel tank see if we uh can find that piece of plastic because i don't see it from the outside flip around here and we'll take a look at it from this side oh hey there's our spring yeah i wonder why my magnet didn't pick up that spring but uh i still don't see that plastic piece yeah i don't know where it went i guess while i'm at it let me go ahead and fish out that spring there we go pull it out yeah so there's our second spring right there all right so after fishing out the other spring for the fuel pump like i said i don't see the white piece that covers the fuel pump module but then again the other thing is that this is not an oem mopar fuel pump this is an aftermarket delphi one still a high quality one but um there are some differences so if you take a look at the location of the actual pump itself this is where the fuel pump is located and if you look on the original one the fuel pump is located right in the center so there are some subtle differences you know maybe in this case probably the aftermarket one might even be a better quality one than this original equipment one so anyway at this point i'm going to go ahead and clip the float onto the side for the fuel level sensor then i'm going to install this pump get the gas tank back in the vehicle and see if this thing starts up all right guys so i've got the new fuel pump installed we have the gas tank up in the vehicle everything's reconnected we are ready to try to start this thing up i'm going to hop in i've got the key in my hand and hopefully we can get this thing to start let's prime the pump a couple times just turning the key on flick the key off put the key back on turn the key on let it prime the fuel pump a couple seconds uh do that maybe two or three times and then finally we are going to attempt to crank it and hopefully this thing starts bam check it out so the engine is running you can see the tachometer right now this thing started right up sounds good i don't feel any misfires and we don't have a check engine light we do have an abs and a traction control light but i think this thing had a code for like a wheel speed sensor we're not going to worry about that this thing is up and running we are back in business that's a fix anyways guys at this point i'm going to end off the video like i always say i hope you found it useful i hope you find it informational educational entertaining if you did make sure to give it a thumbs up if you haven't done so already make sure you subscribe to the channel hit that notification bell i'll see you guys in the next one thanks [Music]

Channel: ADVANCED LEVEL AUTO

Views: 425,826

Keywords: dodge ram trx, ram 2500, ram 3500 dually, ram 4500, fuel pump replacement, fuel pump problem, fuel pump symptoms, no gas, no diesel, gas pump, engine stalls while driving, engine stalls when idling, no fuel pressure car wont start, how to replace a fuel, how to replace a fuel pump, fuel filter, hemi, 5.7, 3.7, 3.6, chrisfix, south main auto repair, scannerdanner, scotty kilmer, how to test fuel pump relay, how to test fuel pump pressure, diagnostics

Id: 51tm7u_Go1g

Length: 27min 54sec (1674 seconds)

Published: Tue Oct 19 2021