Tpms reads. 39psi LF. RF. 38psi. Then 0psi LR. RR 0psi. When I let air out front tires it doesnt change . When I let air out of rear tires , the psi for front tires drops.

 

The problem is NOT Remote start, that was just a test.

The main problem is getting the TPM positions reset.

The car was evidently a fleet purchase without RKE.

2 of the TPM sensors were replaced.

And the TPM setup has to be initialized via Tech2 (or computer). After it is initialized the EL-50448 might work; but getting it initialized without RKE is the problem.

 

I had 2 new sensers put in front tires at "action gator tires" and they couldnt get them to program/initialize.

 

Ah, I wonder if they put incompatible sensors in. Is that a possibility, donbrew? Is there such a thing?

 

Hmm , I believe there are different megahertz sensors, it is possible they used the wrong one

 

Dam it Jim! We need that Tech2 Tricorder!!

 

The one Discount Tire installed in mine is 315 MHZ. Jon, do you have paperwork on the sensors from Gator?

 

He hasn't got to the point of finding out if the sensors are the right freq or not. He can't get it into learn mode because it was ordered without. The UJM RPO code is for "tire pressure indicator manual learn" which means you need to manually set the positions with something like a Tech2 vs. "computer learn" like we are used to or "automatic" learn like some earlier systems used, I THINK, I CAN'T FIND A DEFINITION.

315 is the correct freq. I happen to have one in my hand right now!

And 125 MHz is used to excite them in learn mode.

 

Oh OK, I missed that he verified he had UJM. Saw it now!

 

Don. This whole thing about what "TPMS have I got ? "can be confusing. I know you and I have had this conversation before about the mid year system change by GM.

Anyhow. My 2010 has the UJM and can be reset without the special tool. If the system was changed during the 2010 production run, then I wonder why it still lists UJM as an RPO code available in 2011 ?

Not sure if UJM is actually the manually relearn or simply just the relearn system that you may or may not need the tool.

I did a little searching online about GM code descriptions. Some define UJM has manual relearn, some just call it the TPM relearn.
Guessing they used the same UJM code regardless of which relearn system you have.