I have visited this topic multiple times but have not been able to get the system back working. When I bought the car, it did not have a fob, I bought a fob and was able to get it programmed and the system worked flawlessly. One day I was working in the center console area, checking wiring to the shift indicator light and HVAC and DIC back lighting......
I guess I touched something and the PKE light went crazy...... Ignition off and PKE light started fluttering and flickering and the PKE system would no longer work. Basic trouble shooting without special tools pointed to the module, I bought a known working module and replaced................ Prior to replacement, no PKE light, no programming mode, nothing......After replacement the system is still not working, but my symptoms have changed. The system will not enter programming mode, but the light will come on and stay on even after key is removed and will stay on for several seconds, up to a minute or so..... When the light is on and the key has been removed and the door has been opened and the light is still on, putting key back in switch will cause light to go off........Attempt programming again and then nothing, no light.... and this is the circle of symptoms......I was curious about other features around the locking of the car and the security key and I have discovered and do not know if it is related, my car will NOT unlock if the key is left in the ignition. The door ajar light and dinger works without fail......the security light functions and responds as designed...... So my question, is the doors not locking with the key in the ignition part of the PKE, in other words, does the PKE have to be active for this feature to work, or is a system that woks separate but linked to PKE system.......

 

Will the car not unlock with the key in, or will it not lock with the key in? Or both? The car is designed to automatically unlock the doors (if locked) when the doors are closed if the key is in the ignition. The fob should not lock the doors as you walk away if the key is in the ignition. I don't know about not unlocking with the key in, you should really have to work at it to get in that condition (if everything is working correctly).
From the owners manual:
The system has a feature that makes it difficult for you
to lock your keys in your vehicle. If you leave your keys
in the ignition and lock the doors, the system will unlock
the doors as soon as they are closed. If you leave the
keys in the ignition and move away with the transmitter,
the doors still will not lock. You should notice that the
horn doesn’t sound and return to get your keys.

 

Leaving key in ignition, locking doors with door lock button, close doors, doors do not unlock.
Both door lock buttons work, both key locks work. The only thing that may be amiss with door lock button is door lock button on drivers door works um backwards..... You push forward to lock and rearward to unlock.

 

Not sure what to say. Any chance the receiver you put in wasn't really working right?

 

We had a problem programming our PKE unit. Bought the car and it wasn't working. Bought a new unit and followed the programming sequence. Could not get it to work. It was aggravating. Then we checked this forum and someone posted that fluorescent lights emit RF signal that interferes with the programming. Our entire 3.5 car garage is lit with fluorescent lights. We turned them off, went in the house and ate dinner. Went back out and used a flashlight to see. Then we could program the PKE successfully. I hope this helps. Good Luck. I truly understand the love/hate relationship with the C4...