: This is really getting old

08-17-07, 03:18 PM
Our 07 STS has been in for the tire monitor system three times and it is still screwed up.:mad: Reads the rears but the fronts come and go. Been in twice for the passenger air bag light not coming on and is still screwed up.:mad: The seat cushion is shifted over about a 1/2 inch from the side of the frame. One time when we got the car back the passenger seat wouldn't operate.:mad:

08-17-07, 03:44 PM
Supposedly tons of problems with TPMS--according to a tech, but all he sees is problems.

08-17-07, 05:04 PM
That's really funny. I had this on my 90 and 99 Corvette without any problems.

08-17-07, 07:08 PM
That's really funny. I had this on my 90 and 99 Corvette without any problems.

Interesting!! I play on the vette forum, and I do not recall seeing any comments about TPMS. Local Caddy dealers seems to deal a lot with these problems. ?????

BMW owners do not complain about them either. Maybe there was a bad batch of TPMs out there.

08-17-07, 09:14 PM
The only problem I've had is when I had a slow leak fixed. Had them rotated at the same time. When I got home, couldn't set the one that they had worked on. Went back to the tire place. Went round and round with them. They wouldn't do anything about it. Ended up taking it to the dealer to get fixed.

THEN I went back to the tire place with the work order showing it had been replaced.

Even tho I really couldn't afford to lose any more, :) I gave them a piece of my mind.

Other than that ... never had a problem woth TPM.


08-17-07, 10:00 PM
The problem, I believe is they keep replacing the wheel sensors, when I think the problem is in the BCM. Their trouble shooting tree probably doesn't tell them to replace the BCM. I have the service manual from my 99 vette and it sucks compared to the way the old ones were put together.

08-18-07, 07:51 AM

The TPM is obviously a transmitter. Therefore it HAS to have a reciever and a clear path from transmitter to reciever. Maybe something is interfering with the reciever.

I wonder .... does the rear TPM and the front TPM use the SAME reciever?

If so, then something is blocking the signal from the front TPM. If not, then the front reciever (for some reason) is not getting the signal from the front TPM. Could be a little piece of foil backed insulation or sound deadener in the wrong place. Either that or the front reciever is bad.

I can't believe that many TPM's were bad. I haven't seen any other posts about bad TPM's, but that don't mean anything.

Next time I am by my dealer, I will stop and ask them about bad TPM's and explain what has happened to you. See if they have any ideas.

Jim from Texas

08-18-07, 09:11 AM
Wow, what a mess this topic is. :D

Okay, first of all here is how the stuff works.

Each transmitter has a unique ID number. Each vehicle has an RCDLR (remote control door lock receiver).
The RCDLR picks up the signals from the remote transmitters (key fobs) and the tire pressure sensors.
The RCDLR then takes the messages it receives from the various devices and transmits commands over the vehicle's communication bus. The related systems then use that information to display data or perform required outputs, as in the case of the keyless entry.. keyless igntion systems.

The BCM, which in this car is really the IPM (instrument panel module) handles most of the outputs, but is actually only a slave in this system that processes the data from the RCDLR.

The problem arises in some of these systems when GM makes sweeping changes... as they have recently done.
Many techs are still having problems understanding how to properly set up an RCDLR.
If the setup procedure is not followed properly the system will never work correctly. We even see some that seem to take the programming but when operated for a while start doing strange things.
On an STS this can become more complicated because of the easy key system.

I can't really tell you what to tell them, but I can tell you that GM made these systems a lot less user friendly than the original systems that were on older cars like the Vette.

The Vette systems presented their own nightmares. The sensors were color coded and they were all the same from car to car. Their operation was really clunky and diagnosis, should something actually go wrong was even clunkier.
The real issues arose from tire rotations, since each sensor was designed to stay in one place (thus the color coding) and sometimes some bonehead would replace an orange sensor with a blue one (or whatever color) so now you have 2 blue ones and no orange one!

Aaaaaaanyway. It is not quite as simple as you might think so be patient with your dealer as much as you can stand. Maybe ask them to have a shop foreman look into the problem or have a different tech look it over.

As far as the PPS system (Passenger Presence System) goes... it is calibrated to stay off until the system sees a certain amount of weight. Many times lightweight passengers... such as a lightweight adult, may be so close to the border of the limit they may not activate the system when they sit in the car.
The sensor could be improprly calibrated but even if it is there still could be issues about the weight of the person and the way they are sitting in the seat. If I put my 195 pound frame on that seat and it doesn't turn on, I usually replace the PPS system and reprogram it. It sounds like they may have replaced it since you said something about the seat not working.

Usually bad sensors are easy to find since they won't reprogram when you go to program the tire monitor system, which is not really rare but not quite as common as you might think.

Hope this info helps.
Sorry about the length.

08-18-07, 09:15 AM
I think that there is a cold solder joint in the receiver. Because the problem comes and goes. It would be interesting to see if there is a dealer that knows how to fix these things.

08-18-07, 09:28 AM
My wife weighs 135 to 140. That tells me that the sensor is faulty. They haven't replaced the sensor, just re programed it. There are three posters on this forum that have the TPM problems. The problem is always with the front sensors. Pretty odd. Speaking of cold solder joints. I have fixed a Direct TV high definition sat box, the digital cluster in my 84 vette, the ride control module in my 90 vette, a vcr, etc. They all had cold solder joints. In the case of the 90 vette ride control, that module would have been $900. Ouch!!

08-18-07, 10:10 AM
I would think connection issues inside the RCDLR would cause a systemic failure not the type of failure you are talking about.
It wouldn't see 4 signals and ignore two. It sounds like a programming issue to me.
There is often updated software available for the RCDLR, did they check for that?
It may not apply to that car.
I know we see a lot of issues with the '06 and up systems on other vehicles, most notably DTS and Escalade.

As I said, if I get in it and it doesn't see me, I replace the sensor. No chance in taking a risk with your passenger's safety. It can be intermittent, I have seen that too.
When it comes to inflatable restraint systems I always go on the side of safety, even though GM might like me to save them money.
You might suggest to them you have heard that some people are having luck with replacing the sensor.
It actually comes complete, module, sensor, and cushion for the passenger seat.
If they indicated that they called GM TAC, their hands may be tied.

08-18-07, 10:52 AM
The problem is that it reads all four signals and then only reads two. Then you may hit a bump and then it reads all four again. Can you imagine how many good tire sensors have gone to the dump?? My tech writer says they replace 20 a week.

Is it possible to just bypass the seat sensor so that the air bag is always on? I can just see an accident and the air bag not going off. Litigation big time!!

08-18-07, 11:33 AM
One other thing. About 3 months ago the car would not remember my presets for about four days. Then everything was fine. Yesterday, the car would not start for me. The wife handed me her keys and I set them on the drink holder cover. The car then started with her presets of course. We go to to get something to eat and when we come out my fob works just fine. Sounds more and more like a cold solder joint to me.

08-18-07, 12:54 PM

Went by my dealer a while ago. He seemed to think, (based on what I told him about the TPM) that the reciever was bad. Maybe that is the module that ewill3rd was talking about.

The dealer said that it was ALMOST impossible that 3 sets of TPM's, all of them on the front, would all go bad. There "HAS" to be something else wrong, and he felt that it was the reciever. That would be the first thing he would have checked.

Jim from Texas

08-18-07, 02:50 PM
It couldn't take more than 20 minutes to swap front and rear tires and wheels and see if the problems swap. I know the sizes are staggered but it won't matter to drive it long enough for testing purposes.

08-18-07, 04:03 PM
I would imagine that the fronts that are now on the rear would not report.

08-18-07, 04:20 PM
I would imagine that the fronts that are now on the rear would not report.
That would confirm the transmitters over the reciever. I think that is what they want to know. It sounds simple to me.

08-18-07, 04:52 PM
The receiver doesn't have a clue as to where the transmitters are. The transmitters are all different, specific to each wheel. It won't make any difference where they are located.

08-18-07, 07:04 PM
Also, this car is not a V Series. So the tires and wheels are all the same size.

08-18-07, 07:36 PM
Also, this car is not a V Series. So the tires and wheels are all the same size.

Not true...

Perf. package STS's all come with staggered sizes dating back to model inception. It has never been specific to the V...

08-19-07, 10:26 AM
The reciever knows where the sensors should be.
When you program the sensors the RCDLR associates the ID number to the position on the car.
Moving the wheels from front to rear and vice-versa might indicate if this is a range or interference problem.

Most STS that I have worked on have different tire sizes front and rear, some models have the same size tires all the way around. I have never spent any time worrying about which ones have which, so I always just look.

08-19-07, 11:00 AM
I'm glad I only have that impractical staggered tire and wheel size on my Corvette.

ewill3rd: What about the problems with my fob also??

08-19-07, 04:09 PM
I really think your dealer needs to spend some time looking at this car.
It sounds like you have a problem with the receiver or some sort of interference inside the car.
You say this is an '07?
I don't really see any bulletins related to this concern.
It would be best if you could establish a pattern and possibly demonstrate these concerns to a shop foreman or a tech at the dealer.

08-22-07, 09:42 AM
Good Ole" ewill3rd. What would we do without him? I only wish someone with his expertise worked at my dealership. Thanks man for your meaningful replies.

08-24-07, 11:37 AM
Picked the car up yesterday. They changed a module under the passenger seat. Maybe that is fixed. They replaced the fobs. I thought that they had probably changed out the receiver. Looked at the paper work and they didn't. They changed out another sensor on one of the front wheels. I hope they are not throwing away all those good sensors. I told the wife that we would get the "Service tire monitor system" before we got home. WE DID!!

08-24-07, 11:13 PM

I know this is not for the STS, but ........... it fits with the problem you are having and what Ewill3rd was telling you.

Another thought..... maybe you need to take it to a different dealer.

Notice close to the bottom of the article .... if step 2 is not performed correctly YOUR TPMS DON"T WORK.

This information applies to:

- 2006-07 Cadillac DTS, Chevrolet Impala and Monte Carlo

- 2007 full-size utilities and pickups, Cadillac SRX, Pontiac Torrent, Chevrolet Equinox and Buick Lucerne

Technicians have encountered difficulty after replacing or SPS-programming a Remote Control Door Lock Receiver (RCDLR) when programming the Tire Pressure Monitoring (TPM) sensors.

The following three procedures must be performed in order, after replacing or SPS-programming an RCDLR.

1. Program Key Fobs

2. Set-up Tire Type/Pressure

3. Learn Tire Pressure Sensors

IMPORTANT: Step 2 (Set-up Tire Type/Pressure) must be done before attempting step 3 (Learn Tire Pressure Sensors).

If step 2 is not performed, it is not possible to successfully learn the tire pressure sensors. The Driver Information Center will continue to indicate that the TPM needs to be calibrated.

Refer to document 1684976 for detailed information on how to set-up tire type/pressure.

Jim from Texas

08-25-07, 06:02 AM
Technically they don't throw the sensors away, they have to keep them until the claim is paid because GM might call them back. If they don't still have them GM will charge the dealer back for the repair.

I would also recommend having another dealer look at it.
It sounds like whoever is working on it is not trying very hard or just plain doesn't understand what he is doing.
I have had problems with these new systems, but not as many as you have seen.
I usually road test them pretty well to make sure problem cars like that aren't going to cause problems when the owner picks them up.

Can you identify what was replaced?
Maybe list me some part numbers and the description on the ticket.
I can't imagine what they would have replaced under the passenger seat.
Did you have air bag issues?

08-25-07, 09:14 AM

The car was in twice for the passenger air bag not coming on. The third time they replaced module KI 14.865 19124201. The next nearest Cadillac dealer is about a 100 miles away. The most important thing was the passenger air bag. I can live with the stupid tire pressure sensors. They road tested it also. I live about 30 miles from the dealership and that's when it came on. I mean the front tires have been off a ridicules number of times. They just don't get it.

08-25-07, 09:50 AM
Did they document any codes or anything like that?
I'll see what that part number is.

08-25-07, 09:57 AM
If they did get codes, I don't know what they were. They called Cadillac tech support about the air bag. Too bad they didn't do the same about the tire pressure system.

09-20-07, 06:31 PM
Well, I think they finally may have fixed it after five tries.:helpless: They replaced the door lock receiver module.

09-20-07, 06:36 PM
We see a LOT of problems with the TPMS systems on the 06+ Monte Carlos/Impalas and 07+ Tahoe/Suburban/Silverados at the Chev dealer I work at.

09-20-07, 08:07 PM
Did I mention I thought they might need to do that? ;)

I hope they got it fixed, I know it has been frustrating for you.