GM Dealer Made Huge Mistake! $500 Diagnosis & $3900 In Repairs!

hey there viewers welcome back to the self made knowledge channel because our 2019 chevrolet it's got the big five three it's got a bunch of lights on and it has no steering and he writes dear eric uh three weeks ago out of the blue while leaving in a parking lot three messages flashed across the dash the service power steering service esc and service trailer brake controller right after that and out of the blue i had no power steering i was able to drive it home and then it was fine for several days it's been coming and going since so i haven't been driving it also a few months ago it tells me it's not in park when it starts and when it is and then it blows the horn loudly when i exit the vehicle this is more of a nuisance than anything but i like to get that taken care of as well so that was a pre-existing problem he had this issue with it you know indicating it's not in park and then he gets out and it you know blows the horn but the new problem is is service power steering service trailer brake controller and service esc that's his new issue he took it to such and such chevy dealership and bath and they acted like it was the first time they had heard of this happening i paid them an exorbitant amount of money to tell me it needs the following part number such and such transmission control module part number such and such rack and pinion and part number such and such trailer brake control module so they they've determined that it needs a new training control module a new rack and pinion which also has the steering power steering control module and a trailer brake control module all are bad i've had an incredibly bad experience over this with the dealer feel like they fleeced me if this is what i need to do to have the truck fixed let's get her done uh but he wasn't gonna do it without getting a second opinion thanks for getting it in i hope you can get me back on the road love always jay so here we are and indeed it has no powers here let me show you what's up of course i don't usually see trucks this new because well they're still under warranty so this thing's only got 47 000 on it you can see it says service power steering drive with care hood open no assist soon so let me fire this pig up and i think just by sitting in it i can tell you what we've got going on so right now it seems to function but this really seems to be electrical load um i don't want to say it if we add electrical load to it things start getting stupid so right now the steering works but let's go like this and get our key jerky with it let's turn on a bunch of accessories put a bunch of electrical load on it usually this brings there we go it's going to say usually that oh you missed it maybe you start putting a ton of load on and that brings up the trailer brake message there we go we lost steering okay so that comes and goes the steering it's fine as long as you go slow let me turn off some electrical load here so if i turn slow it's funny i'm over here jerking the wheel like an idiot and we turn it slow when the trailer brake light comes on our trailer brick message but like i said if we turn slow we do have power steering assist that's when we try to go fast that we don't and there's a shift to park message when we can see we have park indicated here and here but if we get out oops it's because i still have the key on let's shut the key off one of these stupid things who misses the good old key so it thinks it's not in park all right so there's all of his complaints in a nutshell so i have just kion engine off we're gonna go pull some codes out of this thing so i'll get this pulled up on your screen here i just let it go through and scan the codes out of all the modules now mind you when this thing came in it was littered full of codes to the point it was hard to decipher through it so i just cleared them out so i could see what you know who's real what's real what's not and here's where we're at uh so our brake system uh we have front brake pad wear sensor or signal circuit not possible an unknown dtc power steering malfunction level one control module this is the one i'm concerned in control module power circuit this is for the body module trailer brake module system voltage so this these are the ones i'm worried about the power control module circuit for that and then the control module circuit power or power circuit here so this is the ones we're going to focus on uh i want to get us a wire diagram and see see what's up first we're going to look at a little bit of data though we're going to take and pop out of the vehicle diagnostics that we're in we're going to go to module diagnostics we're going to pick the power steering control module and then we will look at some data i think we're going to find that we have a voltage issue here okay so let's see so there's our battery voltage for the module the 13.4 because this tells us how much current is being drawn in it uh before we even pop into anything let's just go turn the steering wheel here i'm gonna take the laptop with us let's just go see what happens here when we yank the steering wheel around okay let me just set this laptop over here in the seat i don't know if we have to have the key on oh my goodness i can't turn crap let's start it that's interesting that popped right down to 11 12 k coming back up wait for everything to kind of normalize here yeah that's it right it's not even running at charging voltage now because our charging voltage look down here in the corner of the screen 13.4 this is only 12.6 i'm gonna turn the steering wheel oh bingo lady there's your problem making grunny noises well that's that doesn't act like a bad uh control module to me because look at that i'm just barely turning the steering wheel as you can see and that voltage is dropping down 7.6 so i wonder well let's see here we're going to take and pop back out here let's go to our trailer brake control module and see because then all we got to do is look at the diagram and see what they have in common and this where is uh brake system where's trailer brake control module we're going to brake system control module uh data there we go okay trailer brake rear axle pant life okay so we'll go trailer brake control data we have voltage here we go there's module voltage okay let's turn the steering wheel here [Applause] oh look at that 10.6 or whatever it just came down to 12.32 so clear clearly it's it's connected here yeah so so when the steering works better so as i steer it lightly now look what it does so it's affecting the trailer brake control module voltage so okay this the show's over folks show's over let me uh do something here here let's turn this thing off so that's kind of stupid that the dealer was going to charge him an insane amount of money i mean granted we haven't diagnosed it yet but let's look at uh because obviously you guys can see the connection here and i thought i saw the connection pulling it in like wait a minute this is doing something funny every time it gets a high electrical demand which electric power steering is a massive electrical draw like if you're looking to induce load on a circuit your car has electric power steering you know you flick on the rear window defogger that's a big drawer you know high beams obviously unless it's led blower motor on high and start turning your steering wheel i mean you can be putting 60 to 100 amp load on a vehicle pretty easily i say we look at a wiring diagram to see where the main power feed is for the power steering control module and for the trailer brake control module and the main ground because we know we have voltage loss or voltage drop but we don't know what side of the circuit that's on is it the power side feeding it or is it the ground side we don't know but let's find some factory wiring diagrams here and see what we can do all right let's see here we are going for electric power steering hopefully it's not overly complicated here let's see so we have let's just look at the main power in the main ground just out of curiosity and hence enhanced so we have fuse 175 amp fuse right there f2 ud and then we have a ground g116 and that appears to be well then this is also the power feed so i don't know what power feed we're looking at when we're looking at module voltage um so let me i'm gonna bookmark this and then we're gonna find uh we're gonna find a trailer brake control module diagram because this may be what we're looking at right here this ignition voltage here in which case we'll have to find on a power distribution diagram are they the same do they come from the same fuse which would be pretty weird if they did gl1 we'll go here i can't fathom what these have in common so trailer brake control module that's what we were just looking at interesting because this runs a 30 amp fuse here its power and stuff is fed from oh it works off a lin bus of some sort and it talks to the brake system control module okay that's quite interesting and it grounds at g405 so that grounds way at the back versus the ground g1 whatever it was up towards the front so at this point i tell you what we still don't know if we're dealing with a power side a power loss or a ground loss so let's do we're just going to bookmark this let's go back to our original bookmark that we saved for the power steering remember that had two fuses right so let's click on this again and let we can test these at the fuse box or the battery wherever it picks up this fuse from its fuse power just so we have some direction so this f2ud 175 amp but i suspect more than likely it's this ignition feed here that it's seeing which that's not a fused ignition that is that is really interesting let me find let me find where this goes where this this ignition feed here is because i would like to be able to check both i know this point is kind of boring sitting here looking at the screen but a lot of automotive repair is just this it's you know forever looking and then uh you know coming up with a plan but uh hear me out on this so looking at the power steering okay so we're looking at this power steering control module and we're we still have yet to determine a couple things i don't want to just go poking wires so if you don't want me to just go under there and just get after it i'd rather not at this point until we we need to come up with a plan so i suspect you know power loss on the main power here the main ground coming in this is your big supplier for the motor we have the ground and then we have this ignition feed here and we the only reason we're looking at these is because on scan data we know that when we turn the steering wheel we see that voltage loss so where where is it reading that from i suspect this right here it says see data communication schematics circuit number 5986 okay let's see so we go to data schematics and then i found it here 5986 is just the the land wake up signal from the body control module so here's our body control module it sends out this signal to all of these modules uh on circuit 5986 i mean that real computer savvy here hold on okay so it comes down 5986 this circuit right here that's the same circuit we looked at on our diagram that was complete for the power steering control module this feeds this 5986 this one right here feeds the suspension control module and the power steering control module um so that's interesting i don't see the brake system control module's a little bit different though that's that's also being fed by the body control module um so this is pretty curious here 5986 comes out i don't i don't know if we have this rpo code or not there's a lot of rpo codes here i haven't looked up i'm curious to know if we go and we let's say for example we look at the radio or the cluster voltage does any of that make sure nothing's out here you know does any of that get kind of silly so let's see if we can just go back to the radio here didn't mention anything about the radio shutting off or anything like that now let's see oops [Music] [Music] [Music] oh well maybe this is a chevy function as soon as i turn the steering wheel the reverse camera comes on maybe that's just a thing uh let's see yeah so battery voltage here appears to be steady too steady 13.5 okay i'm just poking and hoping here folks i'm just trying to gather some oh yeah powers here just completely shut down 100 got no steering now okay at this point i guess i'm ready to do some testing i think i've gathered enough data to see we're gonna find the connection here i can look forever but i think what we need to do is we're going to pick the easiest thing that's broken power steering module i think is going to be the easiest thing to get to we're going to go and see are we missing power on the on the big cable are we missing power coming in from uh the body control module which we now know where that comes from or are we losing ground once we found that find that out then we can really hone in on just a single circuit and then we should be able to come up with our answer here is the connector for the oops man now flashlight gravity here is the main connector for the power steering control module and i see the blue with white wire on it right here on the back side for white yeah white with a blue stripe and then here's our other two our big power in our big ground i'm going for this one first because i want to see i want to see what i want to see i'm going to back probe that we're going to see if we have voltage loss just going to the module right there if not we're going to come and see what we can do with this connector to see what's happening there i have our the negative lead hooked right to the battery negative this is hooked underneath there okay so we can see we're at 13.3 volts um let me see if i can leave this lane on the ground well i guess i'm going to need somebody to help me because i need somebody to start it up and steer it and then we can see if we're losing voltage here can i employ a helper um yeah and i cut out some bad news for you are you gonna go up what are you gonna help bad news what's the bad news about those tires there is eight weeks till production mother okay go ahead and start it trinity oh look at this folks we might be on to something already hey trinity can you turn the steering wheel like slowly like just slowly start turning it like about that fast okay just keep doing that for me are you turning it honey okay turn it all the way to the left is it getting hard to steer it's hard to steer let me see what it feels like sweetie it's like oh that's that's really not too bad right now um kind of jerk it back and forth like that so it feels funny [Music] okay just a minute trinity we need to see up here what's happening make sure that it's still broke here okay start turning the wheel slowly [Music] okay just a second i'm gonna put a little more pressure on the front tires here okay try try turning it all the way to the left okay just a minute okay go to the right [Music] okay just a minute okay so we see it dropping here okay go to the left [Music] okay go to the right [Music] okay that's good sweetie go back to the left okay all right that's good trinity um shut it off first just take your foot off the brake and just push that button looking at diagram so we just did that single power wire coming in now i tapped into the ground it's because i don't see this power steering control module diagram is complete this is all communication wires and then this is all just wires going to the torque position sensor so i i back probed into the ground and then hooked to the battery negative because i want to see is there a voltage drop on the ground side we've got our meter here hopefully we've got a good connection on there so what's curious is we already have 121 millivolts of voltage drop on the ground side we don't even have any current flowing through it yet push on the brakes honey and then push the start button [Music] okay so we have 200 350 millivolts of voltage drop uh let me set it down a little bit so she has some tension on it here i'm gonna set it down a little bit [Music] okay slowly start turning your steering wheel [Music] okay uh back to the right just keep turning it all the way to the right oh yeah look at this we are five volts 1.2 volts one volt okay back to the left three volts there it is this should be at or near zero okay back to the right or back to the left honey keep turning to the left keep going [Music] yeah i mean we're at almost a full bolt there this meter is wicked slow too so i'm sure we're not catching it keep going left keep turning keep turning [Music] yeah we're almost at a voltage drop just on the ground side is it is it really hard to turn sweetie oh okay uh shut it off okay now step on the break turn it back on okay does it turn now [Music] okay just a minute it's a little easier or is it still hard okay just a second i mean yeah look at this we're at an idle at 1.5 volts voltage drop okay good don't worry about it let's see just shut it off here we sit car off we have one volt of voltage drop on a circuit that's hardly flowing any current so now we have direction now it's just a matter of of logic and and working the system backwards so we know that we were tapped into this ground as g116 and curiously enough i don't it doesn't have a g116 does not have a connection with our trailer brake so let's go here let's um let's see what else hooked to g160 i imagine it's by itself that's a that's a big old stud so let's see g116 let's just be sure see what else hooks to it and then we just need to follow backwards is it g116 or is it what is everything else that's hooked to it so parsing control module only [Music] g116 um so yeah that's the only thing that's hooked to that i'm going to take and follow this backwards and see where g116 is then we're going to follow it because i doubt g116 itself is bad because we have the problem with the control module i assume whatever bracket or frame or whatever this is hooked to that entire piece has probably lost its ground if that makes sense to you you can look here and see that service data it's not very useful g116 in engine compartment center not super duper helpful dude how about this how about that's super not helpful let's go back to our bookmark let's look at the ground for the trailer brake controller and just see if if that's an easier ground to find and maybe find some connection there so we have this g whatever this is that's true control switch this g435 i think it is over here boy usually the g and the 400s are away at the back of the vehicle i would be surprised of the of its connection here so g405 now i'm just making a big assumption here i could be this is a big mistake you could make we may have a totally separate problem with a trailer brake controller i doubt it but g405 let's find out where that little guy lives g405 is number three on this diagram number three so that is this is way at the back of the truck yeah and it appears to be i don't know if is it the frame rail that it grounds to there number three yes that grounds to the frame so i mean gosh if we lost the ground on the entire frame i mean that's easy enough to check we can do a voltage drop check on it that would be pretty suspect that we're only having a couple issues here it doesn't take much to run a voltage drop test on that let's just do a quick voltage drop test on the frame rail which i think would be insane if we lost that and only we're having a couple issues would you be so kind as to help me help you we're hot on the trail babe on the trail we're still hooked to the battery negative here we'll grab this and probably the easiest thing i'd be surprised if this whole frame rail is not grounded but let's see here seen weirder things oops oh we're pushing lots of buttons here gotta get it where you guys can see it i'll reach in and touch the frame rail we should be at zero volts okay now we have a freaking half a bolt on the right side frame rail wiggle the steering wheel to the right let's go start turning it to the right look at that turn it to the left oh just a minute did you just lose power steering hun it did okay try turning to the right yeah no kidding look at that two two and a half bolts on the whole left frame rail of the car that's good vanessa wow you're not gonna believe this [Music] yes ma'am who else am i talking to i don't believe you can you believe we're missing ground on the entire frame of this truck 2019 chevrolet and you know what you know what the chevy dealer was gonna do this guy i don't want to guess new power steering control module new trailer brake control module oh there's some of that yeah there's a whole list and they said he charged them an exorbitant amount of money already and a new rack and pinion and transmission control i don't try to break from the module they just [Applause] poke and hope man they don't get paid to diagnose so that's what you get you get a list of parts you need that no warranty even i don't know it's a 19. that's what i got it's less than 50k so i don't know we just got a bad connection boom wow i gotta get up my big nose and find this bad wire nip it out yes ma'am be honest with you i'm a little excited and a little disappointed all at the same time disappointed that you know gm didn't really check it before you know condemning all these modules for going bad and i mean realistically any guy that works in the shop should know that's straight up ridiculous they all didn't die at the same time i believe once we fix this it's going to fix the steering issue in the trailer brake issue but we may still have the whole you know you left your car out of park issue because that sounds like that was pre-existing so let's find out where this frame gets its ground from because clearly we're missing ground on the entire frame and i'm just baffled that this is the only problems that we have because i thought there was a whole lot more that grounded to the frame than than these two issues that we're having i'm going to do some poking i might just do a visual inspection to see i mean we got to be looking for a main battery cable here at this point or battery cable goes to body body goes to frame something like that we're looking for a big component so let's try to find it well i don't know if this is it or not but i wanted to look i didn't want to get the money shot so the the negative battery cable comes obviously from the negative post it goes up here to the firewall it looks like now i get sorry about the sucky part i gave this a little wiggle that seems tight but then i look down here because it is a 19 so trucks get pretty old for new york so it's going to be rusty and crusty and i look down here and i see i see that braided ground strap from the firewall to the engine block but then i see down i see down below and hints and hints running hints man this camera's got a sensitive focus i see down below way down yonder depends i see a great braided ground strap down there that i think probably belongs on this stud up here and hence what the frick everything's in my way um let's see so there's where the one hookup is i think that one below it i'm wondering that one with the rusty brown ring around it i wonder if that is uh where that other ground cable goes so let's have a look underneath it because it's kind of weird seeing this little sucker laying down there right and i think that goes to the frame and probably went up here to the body wow so let's have a little look-see so there's where it looks to the frame and where that's to go back here come on i guess we're going to stick our light up here because it looks like it's connected bear with me folks gotta get a little rough here oh yeah this sucker is connected all right so it doesn't go up where we thought but that could be a crappy connection there [Applause] i mean it almost has to be right or it's crappy right here we could do a vulture drop test on just that or we could just unhook it right here and clean it up because this is the most likely culprit because that's relatively clean up there but i don't think the cable is broken i'm gonna set you down we're gonna get a tool here and loosen this up the bolt wasn't loose let's just see if oh look at this freaking thing here's your problem lady you got a crusty wire freaking junk look at this thing folks not a piece of crap huh yep wait til everybody starts driving their electric cars this should be a real show in new york yeah [Applause] so yeah this whole thing's nothing but just freaking solid corrosion well it needs a new ground strap from here to there unfortunately that's that's the main ground i wonder how much stuff is going to get smoked when it starts pulling current through things it's not supposed to pull current through awesome i went ahead and just pulled this sucker off all the way i'm not putting a braided ground strap back on it should i be more than likely if i want to fix it you know oem style we should be putting a brady ground strap back on it they're better for movement they carry more current than its equivalent size in a you know a braided or a insulated wire but the fact of the matter is this guy's going to be right back in this situation as silly as it sounds i'm going to put a just a 4 gauge you know 14 inch ground strap on there with two eyelets on it i don't think we're gonna get enough movement out of this thing you know until the cab rots and settles but at that point everything's touching so then it's good you know right or wrong criticize me if you want in the comments if it was my truck i'd be putting a solid ground wire on there i see a lot of other braided ground wires on this truck it really makes me wonder this body style truck and the salt belt these are gonna be a problem you're gonna be put out a bolo on these babies because you're going to be on the lookout for them the one that runs around the back of the engine looks like it's going to be the same issues and the other ones that i see these are great they're not great for high salt water environments simply because they hold the water they hold the salt turn right to pus and you know there's your problem lady so that's what we're doing my napa guy just showed up he brought us this little guy right here but i can't see it that's your classic 7-eleven 294 solid cable let's get after it so it's pretty tight there i already wizzy wheeled the frame it's kind of hard for me to get my head in there and you but i put it so it's going to have a little bit of a u in it so if there is any flexing there's not a ton of at least it'll have some give to it but it certainly will outlast that factory one that was in there [Music] there we are folks so there's what it looks like from down here like say if it was my truck i would do the same thing i wouldn't put the braided stuff back on it just because that's just more problems i'm sure we generated an insane amount of codes while doing this so i'm going to go through and clear all them out then we'll start it and see if the problem solved let's see i've got the codes cleared in it i'm going to take be curious to see if it fixes his you left your car not in park problem shouldn't have any lights on here okay there we go one thing i did want to see which i thought was weird before i know i'd yeah so that was screwed up too because when i would turn the steering wheel before the reverse camera would come on so that's pretty interesting i didn't know like i mentioned earlier in the video if that was a gm thing because i don't work on too many of these new cars or or what but yeah before when we would turn the wheel just a little bit every time we touch the wheel the reverse camera would come on so that was something worthy of noting but now we're in good shape i think all that for a silly little ground wire cool oh let's see if this park thing is see if that still screws up on them that time it worked [Music] he said about every 7 out of 10 times that that would screw up about every time that we did it in the shop it was goofing up but hmm [Music] maybe that's fixed too [Applause] so that's good this fella will be happy [Music] yeah whatever we're going to keep on keeping on so easy fix on this one folks unfortunately for the general motors dealer who looked at it made a huge mistake huge diagnostic mistake uh overlooked you know the super obvious problem that was glaring red ass which was the voltage loss and then just from that point tracking it down is it on the power side or the ground side and then just picking a component to figure that out on i knew the power steering control module was the easiest thing to get to and i also knew from evidence looking at the scan data that it was losing voltage i mean it was clear and obvious that when we would turn the steering wheel things started going kind of stupid and like i say the power steering is a giant consumer you know that's going to consume you know it's on 175 amp circuit so it potentially could you know take that much current so just you know simple logic follow it down lead you to the problem i believe that gm should give him his money back though the guy's over 800 into this at the dealer because they charged him restocking fees to send all the parts back that they were gonna you know shoot load in their parts cannon so he had to pay for their ammunition plus he had to pay a 500 diagnostic fee for something that was improperly diagnosed it was clearly not the right answer so i hope that they do the right thing and you know now that he has some proof and some evidence like you know here's what the problem is and maybe you know the guy that worked on it can learn from it and say well if i get more of these in the future i can at least throw one of those ground cables on it or go there and give it a tug and see if it's broke i know that's what i'm gonna do when i get a customer that has one of these and everything's gone wonky i'm gonna go right there and just have a visual inspection is this ground cable garbage yep here you go here's your problem you know slap one on it move on with life why don't you guys move on down to that comment section down there leave me the comments hit the subscribe ring the bell let me know what you think gm should do for this fella if anything and um just remember viewers if i can do it you can do it thanks for watching [Music]

Channel: South Main Auto Repair LLC

Views: 804,921

Keywords: power steering, electric power steering, steering, power steering problem, power steering problems, how the electric power steering system works, silverado electric steering, no electric power in car, power steering inspection, power steering service, power steering cleaner, how the electronic power steering system works, power steering fix, power steering pump leak, sticking power steering, power steering control module, power steering fluid leak, hard power steering

Id: 8CFZcO4NDhI

Length: 39min 26sec (2366 seconds)

Published: Fri Aug 26 2022