I am having major troubles with the RFA devices on my 99 c5. My tire pressure sensors and keyfobs have just stopped responding since I purchased this car about 1.5 years ago. Since then, I have replaced batteries in the old fobs, bought 3 new fobs, broken the tires down and checked the pressure sensors, and replaced the RFA receiver. My service manuals directed me to check the serial data line for continuity. I checked it at the RFA receiver and at all devices that the RFA communicates with, the bcm, pcm, ipc, scm, ldcm, rdcm, and I can find no broken connections. I have even checked for continuity at the DLC connector. I have a good ground at the receiver and 12v positive constant. By the service manual, all indications point to a bad receiver, but I replaced it too and I still have the same problem.

My IPC does give me history diagnostic trouble codes for lost communication with the pcm, bcm, and ipc. It also gives one for no tire pressure sensors programmed.

I have checked everything I can check by the manual short of having a dealer hook up a Tech II and see what they can find. I still can not get the car to accept keyfob and TPM programming.

Has anyone else been through this before? I am at my wits end. I just don't know what else I can replace or check. Can you guys help me? Thanks in advance. I really appreciate any feedback.