In this video I have a look at a 2017 GMC Denali that came in with the "Service Suspension System" light on. It doesn't take long to find this truck has been "touched" in all the wrong places and is only a short time away from the crusher.
-Enjoy!
If an SMA Video has helped you out please consider giving using "Patreon" to help support us. The videos take real time to create and pull us away from real work that pays our bills. CLICK HERE: https://www.patreon.com/southmainauto
CHECK OUT OUR "SMA SWAG" STORE! Go on Teespring and get your very own SMA merch!
https://teespring.com/stores/the-sma-store
If you don't like Patreon feel free to use the "PayPal Me" link: https://www.paypal.me/SouthMainAuto
The South Main Auto Amazon Store:
https://www.amazon.com/shop/southmainautorepairavoca
AES Wave Automotive Diagnostic Tools: https://www.aeswave.com/cart.php?m=affiliate_go&affiliateID=2525b91fc8e906e8215984074c9d9e8f&go=https://www.aeswave.com/Miscellaneous-p9347.html
Thank you for all the continuing support!
--Eric & Vanessa O.
Feel like sending some swag to SMA because you love the videos but don't know where to send it?
Just ship it here:
South Main Auto Repair
47 S. Main St
PO Box 471
Avoca, NY 14809
Disclaimer:
Due to factors beyond the control of South Main Auto Repair, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. South Main Auto Repair assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. South Main Auto Repair recommends safe practices when working with power tools, automotive lifts, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of South Main Auto Repair, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained.

There viewers welcome back to the self made auto channel. That's a 2017 chevrolet, it's a gmc, actually denali, it's the 1500 and on the dash it says service suspension. So whatever that means, i let her scan and we're quickly brought into a here's. Your problem, lady situation, because, first of all, why does a car need this many freaking computers to run down the road and uh? The other problem is, is right here the suspension, control module.

She is lit up gray, which means uh non-responsive. So we take a look at this. It's gon na we're gon na see that we have a no-com. So that's our problem and by that's our problem i mean that's our problem in the sense that we can't even talk to the suspension control module wherever it is and whatever it does is to be determined.

So we need to figure out where this thing lives. It's a vehicle, i'm pretty unfamiliar with uh, but we'll look up we'll get a component locator, we'll see where this module is and we'll handle it. Just like we do anything else. Does that power do they have grounds? Does it have the ability to communicate, which i assume it probably does, because it shows it here on two data networks, so it shows on um the high speed controller network.

So, along with the looks like a power steering control module, the electronic brake control, module the steering angle sensor and then the suspension control module, then it also shows it on c-can, which is the purple data network here, which is pins 12 and 13. At the data link connector and if i remember correctly on the general motors that is also i think commonly referred to as the chassis expansion bus, so i don't think we're probably dealing with a broken network wire or you know, a module. That's pulled down killing the whole network because it's only one thing: it's not jibber jabber and on there, according to the internet. Looking like this is the rear of the vehicle.

That's the right, rear tire and looks like it's on the right side. This is the donger that you stick your rod into to let the spare tire down so very similar location as the fuel pump control module a lot of these chevy's that we do that sit back here and have a tendency rod out, get full of water. So maybe the same thing uh, i think, while we're right here we'll try to find a wiring diagram on this little fella. So we know what to check for when we get back there or perhaps we can start out our day with a classic visual inspection.

Hello, hello, huh, hi, luna, hi, pokey, hey wiring diagram is obtained. It seems like a pretty simple one: there's the truck farm truck diesel fuel tank in the back denali, pretty fancy farm truck huh. Let's throw the battery charger on this little felon before we get it up in the air just because, with the key on it's got an og battery in it. So it's probably not going to last a long time, uh kion engine off, and i don't know what we're gon na find when we're in there.

As far as how long we need to leave the key on, i mean we could lift it up and be done in five minutes, or we could be down there for an hour. Who knows being careful not to ruin the element of surprise. We will walk back here together and that must be it. So that's the module and we got a zip tie.
Oh boy, we got some other modules here, probably trailer, brake and fuel pump control module would be my guess. This is your typical new york rock box. I do see some zip ties. We see some fresh tape.

Oh boy. What do we got up here? Let me tip this down, so i can see what can you guys see? Oh baby, this ain't, this girl's? First rodeo. Let me tell you what no matter what she tells you she's lying. So, let's just give it a touch here.

Let me set my light down because it feels smoldering hot feels a little crusty on top, though let's go get a mirror. Stick this right here! That's something that's magnetic we'll go up here and get us some mirror. Here's our diagram. Let's get this little fella before we start fiddling.

Let's have a look up top, oh dirty yeah, so she looks pretty crusty up there. I don't see any green puffs coming out of it, but you know what we got to do next, because she's been taped a lot of sin under that black tape. I bet um. What we should have done is see where the fuse was first and check the fuse, but we're right here so we'll just make some quick checks which is completely backwards of how you should do it, because technically we should have looked before we picked it up.

That would have been the proper way. Let's just take it, we know it doesn't communicate. Let's see, we've got any pin numbers, maybe on the back here. Yes, we do yes, sir okay, so can you guys see the connector here? There's numbers on the back.

We've got our diagram and our ground is number 47 here, and the power is 32 47 and 32. 47. Is this big sucker right here and 32? Is a big red sucker up there? So we have power and ground. We've got a big test light for ampere.

Very jiggly and we have no light and, like my wife, this fuse is supposed to be not at all times. So are we missing the ground? Are we missing the power? So, let's just keep it in the power side, so keep it in 32 and stick it on the crusty frame. If i go up there and stinking fuse is blown, i'm gon na be upset. Well we're still gon na figure out.

Why but anyhow yeah, so it appears we have no power here. I don't know if we have a ground because we have no other power source. I don't think run into this little fella that it looks like no sir, all right. Let's let it down and check fuse what an idiot this guy is because now we need to know uh e-s-c-e-l-h-e-x-h fuse electronic suspension exhaust something else.

Electronic leveling or something 30 amp fuse under hood fuse box left side of the engine. Let's go no erico! You disappoint me, go ahead and say it folks. I believe it sometimes we preach it. We just don't do it uh, so what the process should have been is to do as much as you can from the driver's seat.
You know with the data that you have make your assessments and then um, you know if you determine it's a circuit code, you know, do we have power here and then you know you just try to save yourself time from raising it up and down and lift, But we didn't, we failed. I failed. I'm not saying this fuse is going to be blown, but we need to know if we have power here, not so number 20 e-s-c-e-l-c and e-x-h number 20, which is figure out. The diagrams here number 20.

boom one. Two three four is this: sometimes these are confusing as to which direction they run here. Um, i'm in there we go so there's that 18 19 20.. It shows it as a 10 amp number 20..

Oh, i see because it's not showing the blanks, oh so 1819. So it's this 30 ampere right there stand by. I did bring a test light. Hold that test light right.

There does this 30 ampere have power on both sides, and it does so we got power. Oh, can you guys? Oh you're, not even in frame what an 8 this guy sucks try this all over again everything i just said blah blah blah we're here at the 30 amper number 20, which is this guy right here, and we have power on that side. Of course, you can't see because i got the big light in the way we have power on that side. We have power on this side.

The fuse box looks nice and clean in here about this fuse yep. So i'm thinking that, under that big mess of tape back there, we're gon na find the answer to this little guy. Now you got ta. Ask yourself if i was a broken wire.

Where would i be well somewhere's in the harvest? That's the answer to that question. So i say we see all the sin right here. Well, i got ta talk to this fella just stand by folks. Okay, this is the factory zip tie that one's cut.

Let's just have a we'll. Do some exploratory exploring oh boy, she's taped up a long ways here, fellas, but i'm assuming that we have a lot of well. What color wire was this red? There's? Probably a lot of them in that harness right side up uh number 20, something or other there number 32 red with light. Green is the wire that we're looking for and then there's some sin right there all wadded up red with light green, so we don't know tell you what let's just look here close to our connector.

This is not. This is not factory right here. We're going to take and pop that just kind of tip that back make sure it's not right immediately right here and then i feel a bunch of stuff wadded up right here makes me wonder: oh there's so much here that makes me wonder: um got some zip Ties here she comes around town, gosh dang it. Where are you broke? Oh girl.

I want to open it up in only one spot that has a harness that goes that way to something else. We can't really pull this down and around i'm wondering i wonder what else runs off that fuse if we're able to use the old fox and hound routine, i'm typically not a big fan of that, because most circuits go every which way we do have a big Open harness right here, so that's interesting. There's no tape on that whatsoever. Just want to stick my face under there.
Let me stick a mirror up there to see. If we see any green pus, oh dirty, i don't see any green puffs. It is a fully exposed harness no tape, no nothing um. This kind of we go wake up.

Looking at the diagram, this fuse looking at power distribution, so we have power, comes into it uh and then it goes down and only goes to the suspension, control module. So that's good: it doesn't branch off to a bunch of different circuits. So what we're going to attempt to do is use a tool about about 15 years ago and i've never once used it. The ect 2000 uh diagnose shorts and open like a pro, i'm, not usually a big fan of these, but we're going to give it the old college.

Try. I believe we hook this up battery ground. It's going to inject a signal that is detectable by this receiver that we run along the harness, and i don't know if the batteries are probably dead in it. Oh no look at that turns on.

I don't know what that means we'll fiddle with it um. It might better the batteries in it are from or good up until 2016.. So that's how long ago - and they were probably worth it uh - you know probably 20 10 or so at that point. So anyhow, we'll go put some new batteries in it.

Um. I don't know how to use it, we're gon na figure it out real fine time to be learning something huh. We could find it the old-fashioned way, but everybody's always complaining in my videos, because we don't use a fox and hound setup. So, let's see, if this fuse here, so we're going to need to pull that fuse out and find the non-powered side of it.

First of all, does that make sense to you so we'll pull this one out, hopefully we're on the right clip circuit. Here we should be, and then we want to find which leg is powered? Okay, so it's this one. So we want to go in the non-powered side of it uh. Let's take it, i'm going to plug this thing in here to the battery okay.

So we've got this plugged into the battery. Oh, we don't want that thing beeping and then we're gon na use. I assume something like this, that we can just shove in the fuse box. Okay and currently, this says open circuited on it on a little indicator here i don't know if i short it if it'll say okay, so it says short, grounded uh.

I'm thinking this transmitter here yep so as it comes down this wire oops and then once we get past we, it should send a signal okay, so that makes sense and then if it was short of the ground okay, so it makes a difference, sound, okay, so Anyhow, i think we got the gist of how it works. Um, i'm gon na get something different to go in there. I think i think i think we know enough about it, that we can just get after it here. Boys stick this in here.
This has got your classic banana jack, stick that in there. So if we take our little receiver, which turned off, we can see that you know this wire is traceable. Now, okay, so it's traceable, so we should be able to go under there and trace it through. Whatever harness it runs out of heading back there, we should be able to find it somewhere and then, hopefully, once we get past where it's open, this thing should quit.

Beeping is what i'm thinking, but my experience with these in the automotive world is that the entire harness turns into this giant antenna, and these things don't work that well, but you know i don't know, let's go, try it out. Who cares? Let's quit talking? Is it broke like right here i want the thunder see. I think i need to see something here, so we're gon na go right in the end of that wire. Does this thing become the antenna now now? I think all the other wires in here are becoming the antenna, though that's why these things never work all right.

Let's i better make damn sure that we're missing power back here, wow the fuse is out. I can't you know. I can't even check that now um. Okay, we're getting a faster rate of beeping.

So no, maybe not - let me play with this here a minute. So this is the harness that runs to the back here and it tells you to use open short pickup, so we're looking for an open which is right here on the side of the tool, wiring harness probe. I guess once you can just shove it in the harness and find it, but it definitely should be should be beeping along here for an open or short, which it is. Oh man, somebody's been through here before look at this thing.

She's all opened up which this is kind of nonsense, because it was beeping in the back quit the beep right there. Here's some more harness, that's weird! It's not beeping along that harness beeping along there. But it's beeping in the back, so it's beefing right here, so we're detecting it right here by the spring, shackle oops yeah that changes the scent that locks in the sensitivity level. Okay.

Now you skip right past. That and like i say you come to the back here, and it still is detecting the signal. I don't. I'd probably have to watch the directions on it, whatever dude, let's just fix it, the old-fashioned way.

You see where that's open right there somebody's been all up under here too. Oh, he got some green crusties right there am. I right gosh take them fancy tools and tell them what you just got to look to see where somebody's met in most cases, which unfortunately they've been all over this truck for some reason. Well, that's not the problem.

It's a problem! Anyways, lucky lucky! Lucky! Look at what i see lady now before you even say it. I know everybody in the comment section who has worked for the phone company is gon na rip me apart for not using the tool correctly or something but and please don't send me a whole bunch of fox and hound tools in the mail. I do appreciate it, but um i'll be honest with you. I can find broken wires, usually 10 times faster.
I have at one point way back in the day back when i first bought that tool, and i thought it would be helpful. I do remember watching the videos and reading the directions on it. Let me go get a tool here and then saying wow. This would be awesome, this would be fun and then i remember trying it and using it only to discover that the entire wiring harness turns into an antenna virtually making the tool worthless unless you can keep the tool a certain amount of inches away from the harness.

Exactly so, you can regulate the type of signal that it's picking up and basically it was just ridiculous to use in the end it just just didn't really pan out in an automotive type. Setting now i know there are literally hundreds and thousands of views that will comment that you do this every day and it works for you and that's great. But honestly, it's just never worked for me. I'm kind of old-fashioned we'll break the system down the old-fashioned way and keep us from going on wild goose, chases.

Clearly, this is because somebody has been here. Look at this she's been all knifed open, oh well, you could really open pandora's box. This thing has been slit front to rear and i'm coming in this ain't, good fellas, not good at all. I don't know why or who was in here or what they were looking for, yikes and yes, i know sewing seam rippers are your preferred harness opening tool because it prevents things like this, but i'm being careful folks, rest assured and again we don't even know if This is the wire we're after oh, my goodness, there's more green up in here.

So i'm going to open this up a little bit more because we need to see who else is broken. Let's see here is the money shot let's go get in close for that? Better enhance and hence, and hence unenhanced so i'll, give you the money shot on this one. Oh there, she is there's that money shot. What else we need to make sure that this green up here is not green on the account that the wires are broke, but just on the account that it's just extra residual dust from this little fella? Oh, my goodness, that wire is nicked and broke right there.

This wire is also knit holy moly crap only we don't even know what that purple wire goes to cat's out of the bag now baby. So that's way up under here somewhere son of a biscuit. I wish i didn't even open this up. Oh, an enhanced got this wire right here.

Dude. This truck is basically totaled in my opinion, because if this thing's like this front to rear this is going to be a continual problem year after year, because who knows how? Many times this harness is nicked up through there. I think this is the second video on chevrolet uh that would have been bought at our local dealer. That would have been warrantied through our local dealer at some point that came in with this entire side harness ripped to shreds.
Remember that video we did. It was uh, they had a missing 5 volt reference or something at the fuel pump control module. I mean this wire has been poked here. It's broke right here.

This wire has been cut right here and right here, and it's broke down there. Another wire right here that the insulation is nicked on that needs to be repaired. Somebody just got in here with a knife and just started waving it around like coming to my knife party. I've never even been to a knife party.

I know this tessa tape is the son of a mother to cut through, but you got ta calm down. My guy so we're gon na just bring our way up through here. No i'm not nicking the wires settle down just getting through that yep there's the other wire that broke. I just want to be able to get to everything.

This would be the one case in which the dealership would say: your car, you know, needs a harness aka, we don't know what's wrong with it and then they would actually be right and it would probably be better off than it was so there's this wire, which I think is that purple wire that we just broke yeah so purple and green. We need to fix it. Oh here's, another wire, that's slit right there. This way right here is cut.

That's a network wire boom that one's broke yeah. That's a data network wire right. There so that one's broke that one's broke, this one needs to be broke because that one's cut through cut down just to the insulation right there. So we have one two three broken ones that one needs to be cut back further, and then we have a few here that oh wait a minute.

Is this another broken one nope that was just green turds on there all these smokies? It should be fixed. No because i think that one's cut through so there's those soup i should grab us a zip tie, looks like i'm talking to somebody who's actually gon na go get me a zip tie, i'm thinking just those two yay who's over there. Anybody nope, i'm thinking. That's it folks, uh.

Let's do the wiring repair on one two, three that are broken and then four and five which are about to be broken at some point in their life. I'm going to open this up a little bit more and do what we got to do. I don't know if this is factory here. If somebody's been already been up in this joint and fixed this wire, those trucks are freaking messed.

My guys what's wrong. With this thing all broken wire, have you already found it? Yes, mrs lowe just walk around always impressed you do yeah. I impress you that much wow wow. What else would i be? Oh, i don't know.

Maybe someday i'll disappoint you, you don't worry. I'm disappointing the people right now. Oh, they can't even see oh girl, it's like just kind of shining in outer space over here. Let me move it around.
I thought they come here to see you no. They come here to watch me in hopes of seeing you. I think this is not what they want to see. They want to see what you're doing they don't want to see this, because i'm doing i'm carrying out one of the most controversial topics uh on the planet.

That's what people like, though they want to see that right. No, i try not to piss people off and if you want to piss people off, you walk around trying not to piss people off on youtube someday. So you know me i'm, like here's. My favorite part of the day and the pissing people off that that's from the dog, snowplowing video, you remember the dog right, you seen the video, oh yeah, show you how the dog does it.

You know my favorite, video and yeah. Let's show the people what we're doing here - yeah, let's piss everybody off right here, you ready folks, i've mechanically twisted the wires and now i'm going to solder and heat shrink them. This is perhaps one of the most controversial topics in the words of david attenborough. On the planet, because all of the armchair experts out there will tell you that you need to have a mechanical crimp connection, then the other armchair experts will tell you that you need to solder it then the other ones tell you to use a wire nut and At the end of the day, nobody knows what to do.

However, this is what i'm electing to do, your classic solder and heat shrink, as they say across the pond solder, because for some reason it has an l in it and i'm just adding lengths of wire to the ones that we've cut yeah. It doesn't look great. No, are we replacing the harness? No. Is it going to work you betcha buddy, so we're doing that we're gon na make the old mechanical connection out of it here and then we're gon na slip over a piece of solder and heat shrink in a tube and we're gon na heat.

It we're gon na let it bond and everybody's gon na go home happy and at the end of the day. I'm thinking that at some point this truck is going to come back and visit us here at sma anywho, because i'm sure this is not the only sin. That's hiding beneath all this tape front to rear. Am i gon na go expose it all.

Look for everything! Nope, i'm gon na fix his suspension light and then i'm gon na ship it hey. Now we can talk to it, so things are probably going to have lots of codes in them other modules other than our initial scan. So what i'm going to do is just do a a full system. Fault scan go through and clear all the codes uh just because we opened up some circuits with the key on and everything's gon na, be a little upset with us, i'm sure i'll leave it up to the customer what he wants to do i'll give them.

My recommendation but truth be told i mean it's a 2017. It's a farm truck. They don't live to see 10 years old more than we had already 17 89 20 5 year old truck so another four or five years. This thing's going to be down at wilbur to pull the bath, not a sponsor, but maybe someday we'll in the future, we'll go down and yank some parts off it as long as it's not this wiring harness.
We should be okay, so we're gon na take and get this all wrapped up. I believe that we got all the wires i got. I got those other two that just had the abrasion on them that were just poked through everything else. That's been soldered and heat shrink and those have been crimped and heat shrinked because we essentially just cut them and stripped them back and put them back together.

So we'll get it taped up all fancy, but yeah. It really is too bad. This is probably a 50 000 truck when it was new or more. I don't know, i don't keep track of truck prices, but i'm sure it wasn't cheap with all the options here.

It's got the leather, the hole in the roof, the chubby rubber and unfortunately, it's been hacked to pieces. Probably at the dealer would be my assumption, but you never know so. She's all put back how we found it boy. It's pretty unfortunate to know that there is a lot more sin hiding under these wires and we're under this wire loom than what we can see because he has been touched on every square into that tube yeah yeah.

So we'll put this thing away again for another 10 or 15 years might revisit it or at least steal some of those probes out of it there just never uh. Never had good luck with this stuff here folks, so we're gon na have to continue doing it. The way we've been doing it for the past 20 plus years, using our peepers and uh logic there, let's go start it up. We should be golden now lawnmower man's out there.

We made it a whole video, oh it's under. Let's see it was popping right up here in the middle before there's the gauges she's a little slow and it would pop right up in the middle, where it says hood open, we're gon na dismiss that and there so uh, no more suspension light. Who remembers the day when a gauge was a gauge not just a screen? She's cleaning green now, folks, uh at least for the time being and yeah back when cars had gauges. That was called the good old days, but that time's long gone.

It's only gon na get worse remember. This is an old truck here and uh the newer they get the more crap they put in them and we just got ta. You know more wires, more modules, more stuff um, so most of it's like infotainment creature, comfort, type crap, but it gets expensive in the end. So that's it! That's the end of this show it was an easy fix.

Easy find. Definitely, you know, probably not a normal issue, but obviously was results of somebody's monkey business through this whole harness - and i even see evidence here under the hood, where everything has been zip, tied and taped. All the way across onto the passenger side valve cover. You can see this thing's a mess.

If i was this guy i'd can this truck. I would ditch it 86. This thing it's out of here. This is going to be nothing but problems, and unfortunately this is probably years after somebody was already in there.
You know somebody didn't just cut this open. Last year you get in there, you start knifing, jamming poking it takes a year or two for all your uh sin to be dragged out to the light, but uh. That's it. Moving on you'll move on to that comment.

Section the questions, the comments, the concerns you have, the insti, the facebook y'all know what to do. Just my reviewers. I can do it, you can do it thanks for watching hey.

By EricO

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.