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Discussion Starter #1
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:
 

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Sedan de Ville, CTS
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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.
 

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2011 DTS Platinum
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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.

Jim
 

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Discussion Starter #6
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.
 

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Bob,

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
 

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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.
 

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Discussion Starter #9
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.
 

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Discussion Starter #10
ewill3rd:
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!!
 

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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.
 

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Discussion Starter #12
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!!
 

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Discussion Starter #13
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.
 

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Bob,

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.

Later,
Jim from Texas
 

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2006 STS V8 AWD, '95 Ford Ranger
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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.
 

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Discussion Starter #18
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.
 

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06 STS-1SG-ACC/HUD-Volant CAI-Corsa Exh-Mesh Grill-ClearBra
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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...
 
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