TPMS Woes on GMC [request for diagnostic guidance]

[Two_Car_Garage]

[Long Post Warning]

Wondering if there is anyone here who may have experience with GM's Tire Pressure Monitoring System.

For a few months I have been experencing issues with my TPMS on my 08 GMC Acadia. Last fall after initial issues (pressure readings showing dashes) I replaced all the tire sensors when I replaced the tires (sensors are OEM).

Issues persisted so I retuned the sensors and replaced them again. Issues continued. These two times that the sensors were replaced were done at the tire shop where I purchased the tires (small local shop).

Third time, I went to the dealer for diagnosis as I thought they would have better diagnostic skills/techs. Also told them my keyfob range was pretty bad. They told me everything was fine and that they had cleared the light and replaced the key fob battery.

Fob Range did not improve and that same night I got the TPMS bulb going again.

I did some reading online and things point out to a bad Receiver Module that receives the tire pressure information from the sensors or its antenna. I called the dealer as this requires programming and they want $500 for labor,parts, and programming.

Is there a way to know 100% that the issue is with the Receiver Module and/or antenna? Or could the senors be at fault (maybe I got a bad batch)?

Anyways sorry about the long post but hopefully someone can point me in the right direction on possible DIY fixes. My goal is to be able to definitively conclude its the Receiver, Antenna or the sensors and go from there. TIA

{goes to do more reading online}

 

[bulldogr6]

I had that module in my GM pickup go bad as well, very similar symptoms , fob was totally inoperable tho

Sent from my E6782 using Tapatalk

 

[jd_1138]

I'd just pull the fuse for the TPMS or put a piece of electrical tape over its warning light. It's best to manually check the PSI anyway.

But it shouldn't be too difficult to replace that module. Get a factory repair manual off eBay in digital format for like $5. It'll show you exactly how to do it.

 

[bulldogr6]

Programming it is the issue. You have to have a scan tool that can save the RKE and re flash the new module with it.

I'd just pull the fuse for the TPMS or put a piece of electrical tape over its warning light. It's best to manually check the PSI anyway.

But it shouldn't be too difficult to replace that module. Get a factory repair manual off eBay in digital format for like $5. It'll show you exactly how to do it.

Sent from my E6782 using Tapatalk

 

[Two_Car_Garage]

I had that module in my GM pickup go bad as well, very similar symptoms , fob was totally inoperable tho

Sent from my E6782 using Tapatalk

Did you do this yourself or had the dealer do it? Do you recall if the module has an antenna or it was by itself?

I'd just pull the fuse for the TPMS or put a piece of electrical tape over its warning light. It's best to manually check the PSI anyway.

But it shouldn't be too difficult to replace that module. Get a factory repair manual off eBay in digital format for like $5. It'll show you exactly how to do it.

There is no single fuse for the TPMS/RKE system (see attachments). That system is powered by the DSPLY fuse which powers a bunch of other components. Tape? I would have to tape the entire DIC to block all those annoying messages/alerts.

Not sure if it's difficult or not but dealer is quoting about 4 hours of labor. It requires removing headliner and a bunch of other stuff to get to this module.

Can you please point me to the $5 factory repair manual you talk about? I have never seen one for my car on ebay. Only hard copies for $300 or so.

 

[protegeV]

Did you do this yourself or had the dealer do it? Do you recall if the module has an antenna or it was by itself?



There is no single fuse for the TPMS/RKE system (see attachments). That system is powered by the DSPLY fuse which powers a bunch of other components. Tape? I would have to tape the entire DIC to block all those annoying messages/alerts.

Not sure if it's difficult or not but dealer is quoting about 4 hours of labor. It requires removing headliner and a bunch of other stuff to get to this module.

Can you please point me to the $5 factory repair manual you talk about? I have never seen one for my car on ebay. Only hard copies for $300 or so.

Hate to say it(because I'll usually defend techs to the death) but the dealer is trying to bone you. It only pays 1hr to replace that module. Maybe another .5 for programming and setup. It is under the very back portion of the headliner, right by the liftgate opening. You only have to remove a trim piece or two and bend the headliner down to access it.

 

[bulldogr6]

It was easier to have the dealer do it as I could not do the programing .

Did you do this yourself or had the dealer do it? Do you recall if the module has an antenna or it was by itself?



There is no single fuse for the TPMS/RKE system (see attachments). That system is powered by the DSPLY fuse which powers a bunch of other components. Tape? I would have to tape the entire DIC to block all those annoying messages/alerts.

Not sure if it's difficult or not but dealer is quoting about 4 hours of labor. It requires removing headliner and a bunch of other stuff to get to this module.

Can you please point me to the $5 factory repair manual you talk about? I have never seen one for my car on ebay. Only hard copies for $300 or so.

Sent from my E6782 using Tapatalk

 

[Two_Car_Garage]

Hate to say it(because I'll usually defend techs to the death) but the dealer is trying to bone you. It only pays 1hr to replace that module. Maybe another .5 for programming and setup. It is under the very back portion of the headliner, right by the liftgate opening. You only have to remove a trim piece or two and bend the headliner down to access it.

That is my feeling too hence my attempt to try to DIY and self diagnose. Problem is I have not been able to find out how to for sure condemn either the receiver or the tpms sensors on my own. I will gladly pay 1.5 hrs as that is very reasonable.

Based on my online research looks like I need part# 20803735. Looking at pictures online I see there is two contacts one for a 4 pin connector and another for the coax antenna (my guess). D

Wondering If I could just replace the antenna? Problem is I can't find a part# for that.

 

[langss]

Since it is no longer in warranty, I would try a different dealer. And if that does not work go to another. I have all the warranty/recall/service done at a Buick/Cadillac/Gmc Dealer, on my 15 Silverado. The closest Chevrolet Dealer is about 15 miles away and I'm spoiled being able to walk home and back if I feel like it. The point is perhaps the Dealer you are using does not really need/want your business. The place I am using really wants the business and treats me and my truck well. You are not bound to use that dealer.

 

[Tonyuk]

You could replace the module yourself and have the dealer programme it, the cost would (should) go down by a fair bit.

The sensors in the wheels are pretty simple bits of kit, i've yet to see any of them arrive bad unless they've been damaged in handling, or by a tech putting the tyre on.

 

[Two_Car_Garage]

Since it is no longer in warranty, I would try a different dealer. And if that does not work go to another.

Yeah, maybe worth a shot. I will try my local Chevrolet dealer and see .....

You could replace the module yourself and have the dealer programme it, the cost would (should) go down by a fair bit.

The sensors in the wheels are pretty simple bits of kit, i've yet to see any of them arrive bad unless they've been damaged in handling, or by a tech putting the tyre on.

Yeah, this is an option but wanted to find out 100% it's the module on my own. But have not found a way. Looks like there is no surefire way for a DIY to 100% diagnose this issue. Don't want to be throwing parts at it (which my current dealer wants to do). I also think the sensors are ok and the issue is on the Receiving End.

 

[Walter_TA]

Looks like the module is 80.00 or so. It looks like the install is not that hard. I would buy one install it, then take it to dealer to program.

 

[bwringer]

It sounds like it's not all that hard to get to, so I'd take a shot at eyeballing the connections on the old one -- maybe there's corrosion, or a loose or broken connection. Or just disconnect and reconnect and see if that improves things.




Those cheap "manuals" on fleaBay are pirated (no idea why fleaBay doesn't crack down on these). No, the FBI is probably not going to knock your door down, but they are not legit. Plus, there's a definite risk from whatever else they load on the media or download files.

Toyota has an online Tech Info Library that regular humans can buy two-day access to for only $15 -- that's plenty time to download all the PDFs you might need to compile factory manuals for your personal vehicles. Does GM offer anything similar? https://techinfo.toyota.com

 

[GNX423]

I think it would be worth running a good scan tool on it. on my 09 Cadillac cts, I was able to scan all modules and will show a history of any issues (no check engine light tied to this). I had the driver seal control module come back as being an issue at one point and the steering angle sensor. you should be able to verify there is an issue with the module when the issue occurs.

 

[lutter94]

Since it is no longer in warranty, I would try a different dealer. And if that does not work go to another. I have all the warranty/recall/service done at a Buick/Cadillac/Gmc Dealer, on my 15 Silverado. The closest Chevrolet Dealer is about 15 miles away and I'm spoiled being able to walk home and back if I feel like it. The point is perhaps the Dealer you are using does not really need/want your business. The place I am using really wants the business and treats me and my truck well. You are not bound to use that dealer.

I recall a friend being turned away from a Chevy dealer that refused to complete warranty work on his GMC pickup. He had to go about an hour away.

 

[protegeV]

I recall a friend being turned away from a Chevy dealer that refused to complete warranty work on his GMC pickup. He had to go about an hour away.

That's horse ****. They can do cross warranty in certain situations like that. I can't imagine they were SO busy they could turn away work. Maybe their cross warranty cost was getting too high for their DSM's liking. Still **** to turn a customer away like that in a remote area.

 

[langss]

I recall a friend being turned away from a Chevy dealer that refused to complete warranty work on his GMC pickup. He had to go about an hour away.

Well I feel for your friend, but I don't have that problem. They used to be a Pontiac Dealer, but since Pontiac went away hence the change. I just had the oil changed and the tires rotated on the 6th of last month for $69. Today I got a flyer from them to do it for $59. Hard to beat that.

 

[Two_Car_Garage]

I'd take a shot at eyeballing the connections on the old one -- maybe there's corrosion, or a loose or broken connection. Or just disconnect and reconnect and see if that improves things.

Yep, that is the plan hopefully this weekend.

Toyota has an online Tech Info Library that regular humans can buy two-day access to for only $15 -- that's plenty time to download all the PDFs you might need to compile factory manuals for your personal vehicles. Does GM offer anything similar? https://techinfo.toyota.com

Yep, You can do 3 days for $20.
https://www.acdelcotds.com/acdelco/action/subscribehome

I learned about that in this forum from another user (can't recall who). I have not used it though since I have been able to get most of the repair information thru my library online for free.

I think it would be worth running a good scan tool on it. on my 09 Cadillac cts, I was able to scan all modules and will show a history of any issues (no check engine light tied to this). I had the driver seal control module come back as being an issue at one point and the steering angle sensor. you should be able to verify there is an issue with the module when the issue occurs.

What scanner do you have? I have been toying with the idea to get one (Autel or Foxwell). The one I have can just read P codes (i.e generic OBDII reader)

 

[GNX423]

What scanner do you have? I have been toying with the idea to get one (Autel or Foxwell). The one I have can just read P codes (i.e generic OBDII reader)

This Is the one I have, Autel MD808pro
https://www.amazon.com/gp/product/B0714GBRZK/?tag=atomicindus08-20

While its a little pricey, it has paid me back in time and effort. I was able to locate a faulty wheel bearing that was causing an issue with the speed sensor and locate a few problems with no check engine light on.

 

[protegeV]

This Is the one I have, Autel MD808pro
https://www.amazon.com/gp/product/B0714GBRZK/?tag=atomicindus08-20

While its a little pricey, it has paid me back in time and effort. I was able to locate a faulty wheel bearing that was causing an issue with the speed sensor and locate a few problems with no check engine light on.

THat's not pricey at all. WHen Autel was mentioned I was thinking about the $2K full function scantools.

 

[GNX423]

THat's not pricey at all. WHen Autel was mentioned I was thinking about the $2K full function scantools.

Agreed, its pricey when compared to a basic $14-$30 code reader.
I think for what it can do, its worth it. I did eyeball the $1000+ wireless touchscreen models with ecu programming capabilities, very nice, but out of my league.

 

[Two_Car_Garage]

This Is the one I have, Autel MD808pro
https://www.amazon.com/gp/product/B0714GBRZK/?tag=atomicindus08-20

While its a little pricey, it has paid me back in time and effort. I was able to locate a faulty wheel bearing that was causing an issue with the speed sensor and locate a few problems with no check engine light on.

Thanks! Will look into it. Basically I am budgeting ~ 200 bucks for this "toy" for our cars.

THat's not pricey at all. WHen Autel was mentioned I was thinking about the $2K full function scantools.

I am actually surprised at these prices and how much they have fallen in the last few years. Probably support is sketchy and code has been "reversed engineered". But hey if it works!