Ok Guys - this is a hard one. Battery in 2000 C5 died over winter storage. No big deal, jumped it to take to dealership for inspection sticker. On the way there I got a "Service Tire Monitoring System" DIC message. OK, I'll just have dealership retrain sensors with the tps tool. Get to dealership, and they can't retrain sensors. Hmmmmm>>> ok car is 11 years old, but has aftermarket chromies with new TPS sensors in them that were installed less than 3 years ago. When the battery died, did the sensors continually try and connect until the sensor batteries died?

Okay, since dead sensors seemed logical, I went ahead and ordered new sensors, taking care to order the "expensive" ones (haha) for 97-2000 vettes. They arrived and before I had them installed, I tried to have car learn them while they were not mounted to wheel; no luck. I shrugged it off to a poor magnet.

Took the new sensors to the tire place to have them install and when they tried to train the new sensors with thier tps tool (with new batteries) it wouldn't relearn. The guy said he could get may the fronts to go, but never all four. I called BS and tried to help him, no luck - no relearn.

OK, so off to home I go, determined to solve this problem. Thinking it's electrical now, I looked for dead fuses (especially 27) but couldbn't find any that seemed to be related to TPMS. OK, Since fuse boxes are opened, I might as well do a PCM relearn to see if that has any effect. Nothing. Hmmm, kay maybe receiver is shot, so I go ahead and do a FOB relearn - worked perfectly. Buy a good pick-up tool with the strong magnet, but still no horn beep.

So my questions are, is there something that got hosed in the PCM? Is a "bit" out of place; does the car need to be put on the OBD computer to have some TPMS reset? It still has RFA 2120 code active and in history. If not, any other ideas or things to try? Have I missed something?

Any help would be appreciated.

 

I am thinking you should try a complete reset. Disconnect the battery for 30 minutes, then reconnect it and give it a try again. It sounds like the receiver may have locked up and is not responding. Removing the power may clear the fault and get it to work again. Just my .02 cents.

 

You might want to verify the RFA unit itself as in whatever connectors are securely connected. Personally I've never seen the one in mine as I've never needed to look at it but I hear its in the rear compartment, left side under the carpet. Please don't hold me too that as I haven't seen it.

 

Same issue here... Sensors dead. Drove the car for a week, bought new sensors... the day before switching out said sensors I tried one more time to reprogram the old ones.
The old ones reprogrammed like they were new. Go figure. Still work perfectly.

Drive it for awhile and try again.

 

Well tried the complete reset, no luck. Have been driving the car around but it still wont recognize the TP sensors. Have looked a the wires going toward the receiver, but pulling the back panel off is a pain. Priced a new receiver but that was over $300 and I already have over $440 in solving this problem with no luck. (diagnostics, 4 new sensors, mounting). Any other ideas? Can this be a computer glitch that I need to have my pcm set with the OBD computer?

 

I might be going out on a limb here but did you check your DIC for any codes???

 

Check for DTC Report ANY.. Does your FOBs lock and unlock the doors and trunk and panic button work??

Relearn the sensors your self again... What magnet are you using and where are you holding it Put the magnet on the part of the sensor that sits FLAT AGAINST THE RIM when programming and see if that makes a difference.

 

DTC is 2120. FOB works fine and can relearn fine. I'm pretty sure that the receiver is working as I stopped by a grease monkey and they had a tps tool and could train the rears but not the front. I Immediately drove home and was able to train the fronts but not the rears. Any ideas? I'm gonna try just driving around for an hour or so and building heat up in the tires and see what happens. Any other ideas also welcome.

 

Starting to sound like the magnet you are using isn't strong enough or not laying it on the wheel right above the sensor.

 

 

Go back to your grease monkey with your magnet so you can train the front ones, let him train the back ones and together you should be able to train the whole set.

 

Well, ordered a "super strength" magnet that came in while I was out of town. Giddy with anticipation that the magnet is the panacea for my TPMS relearn woes, I quickly opened the package. Sure enough, the magnet should have a big "WARNING- DANGER" sign on it it is so powerful. Need to make sure I keep it away from any of my stuff.

Long story short, put car into relearn mode (knowing that I have 4 new sensors and I have heard each of them "chirp" the horn at one time or another) and BAM - NADA, NOTHING, SILENCE, NO CHIRP. WTH!!!!!!!!?????????
I am scheduled to got to another GM stealership tomorrow to have them try and relearn the sensors. Anybody else got any other ideas before doomsday?

 

Are you using the proper sequence to train the sensors...???? I dont understand how anyone can get the back ones to train without going throught the proper train sequence, and not only that you only have a limited time in the sequencing to train each of the sensors. And you have to train them and get the confirm horn beep as each corner is confirmed.

 

well the car doesnt really know "what" sensor you are starting at, so if I put it into learn mode and the dic reads learning left front, I can put the magnet on any wheel and if the car RFA receives the signal it will think that its the front left, regardless if it is or not.

Like I said I have heard each wheel chirp, I have guy at the tire place with the correct j tool able to train first 3. I do not think it is bad receiver or bad sensors (they are new).

 

You are correct in the fact that the receiver doesnt know which corner is being trained.. but sometimes the simplest thing can be over looked, thats why I meantioned it..also keep in mind that you have limited time to learn all four corners...and as Bill C has already mentioned the tool, ( Magnet is nothing special ) I used a simple pocket pencil magnet... getting it as close to the base of the valve stem is critical. the only other thing I can think of is the possibility of a bad sensor, although I though I read that at opne time you could get the two front to learn, and then said at another time you could get the back to to learn... this would point to a time out issue of the last sensor trained.

 

Yes, I'm definitely timing out. I've been working tonight and can get the left front, but not the right front. Im pretty sure the magnet that I'm using is strong enough as it is DANGEROUS to get it anywhere near ferrous material. I removed any rf interference type things I could find around the receiver. 4 new tp sensors were installed. The only thing that I can think of is the original installer was trying to train the sensors with a non j146 tool (newer tool, NOT the donut magnet one but a regular tps trainer. He was able to get the fronts to chirp,. Grease monkey had the same tool and was able to get the backs (out of sequence attempt) to chirp. NTB had the correct tool and was able to get all the way to the final back left before timing out.

 

The ID's of the learned TPMS are stored in the RFA itself, so the PCM is out of the loop after programming. Once you have one or more tires programmed, do they all continue to update pressures on the DIC? Or do they go to "XXX"s? FYI the magnet will force them to transmit the pressure if they go to sleep after parking for a couple minutes.

Does that RFA B0-2120 code continue to appear under the DIC? If you clear it, does it reappear immediately or after some time? Make sure you have cleared at least the RFA codes using the DIC. If you have an RFA represented in the DIC codes (and your keyfobs are working, right), the cabling to the RFA is working properly.

Make sure to address any of the "errors" presented on the DIC that you normally have to press the Reset button on. I was having similar troubles training two different sets of '00 TPMS on my 2002 (with the older RFA). I believe it was due to a "chatty" OBD bus interfering, caused by frequent messaging from:

- Driver Door Ajar alert
- Toneau cover ajar alert
- Battery voltage fluctuation (I had a charger on while I was poking around, trying not to kill the battery)

These were verified by sniffing the OBD messages from computer to computer while attempting to train. The voltage fluctuation was the chattiest, broadcasting a new voltage every second or two. When I closed all the doors, removed the battery charger, cleared codes, then did the relearn from outside the car, it all went perfectly.

Usually within 3 or 4 seconds of applying the magnet, the horn should chirp. On my '00 sensors, I applied the magnet to the "barrel" of the wheel over the location of the TPMS module, not by the rim lip next to the tire bead. I used a $5 beach comber's magnet.

Hope this helps.

Todd

 

I have seen NEW sensors be defective from the factory. Its possible and it sounds like it is. Put the car into train mode and try ALL the sensors, if one does not work move to the next, if the other one(s) work you have a bad/defective sensor, period. If you bought them from the dealer they should replace it for you.

 

Todd

EXCELLENT info! Thats what I was thinking. Make sure ALL the DTCs are cleared. close all the doors and make SURE the battery is FULLY CHARGED before you start the procedure.

BC

 

Thx Bill - I'm honored to be recognized by the master! Here's hoping we can solve the OP's problem.

Todd