I had an instance with my 2009 HHR LT where I had lost both my FOB control and my TPMS readings. Naturally the TPMS warning light was lit. I took it to the dealer for the firmware update as mentioned in several other threads. The tech told me that it appeared that my receiver, located above the headliner/mirror, appeared to be bad. OK fine, I'll change it.
I ordered a new, identical, receiver and installed it in my HHR. Not a fun job but it only took about 30 minutes. After I installed the new receiver I powered up the vehicle with an OBDII plug in used to program key FOBs. I programmed all of my key FOBs and now they are working fine so that problem has been addressed. Next I had to take care of the TPMS.
I held the lock/unlock buttons down and I got the expected two horn beeps. I went from tire to tire, as instructed by the manual, and let air out of each one until I got the horn beep. After I had a successful beep on each tire, I got the two horn beeps after the last one to indicate that the relearn process was finished, and successful. I aired up the tires to 30psi and drove the HHR for several miles. My TPMS warning light went out, but all I had was dashes for ALL tire pressures.
I got home and used my TPMS sensor activation tool and went through the TPMS relearn process again. After the two beeps to arm the system, I went to each tire in order, as per the light signals, and received a beep after each one. When finished with the last tire, I again got the double beeps indicating that the relearn process was successful. The TPMS warning light has stayed off and I still do not have any pressure readings from my wheel sensors.
I should add that these are all new TPMS sensors that are GM #13598771 sensors that I replaced. I ASSUME they are each communicating with the ECM since I got a beep after each one was activated/relearned according to the manual.
Obviously I am doing something wrong or my pressures would be showing. What puzzles me is that my TPMS warning light remains off and the relearn process seemed successful each time but still no pressure readings.

 

To begin the software update is for 2008 models.
Then, the new RCDLR needs to have it's software loaded.

 

Follow the relearn it’s listed in your owners manual
Donbrew has a link in his signature.

 

I made my way through the wall of words, he did relearn. The positions are set, the BCM doesn't know what language the RCDLR is speaking. New RCDLR don't have the software loaded.

 

As I mentioned, I went through the relearn, according to the manual, twice, using my TPMS activation tool and using the air pressure method. My vehicle was built in late 2008 so that is why I asked the dealer if there was the firmware issue.
My remote control door locks are working as designed and the vehicle goes in to the TPMS relearn process as per the manual. The TPMS warning light is off. Would it do this if there was NO software loaded in to the receiver that GM gave me?

 

I wasn’t sure , till Don pointed the reprogramming of the new part.
my thoughts were about which tire you start with.

 

I went LF-RF- RR-LR and I got the double beeps.

 

I find it difficult to believe something caused the RCDLR to break to begin with. I had a "technician" swear that there was no module in my car; his Tech2 couldn't find it. He was an idiot.

 

Ok, that confirmed my theory.
a new flash is required

 

The important part seems to be the tire type/pressure..