Question: My 2005 Cadillac Escalade EXT was rear-ended and I had it repaired at a good body shop. Everything looks great, except the rear parking assist stopped working. They replaced everything including sensors in the bumper, wiring, and module. They can't figure it out. What else could be wrong?
Answer: The rear-object sensor-control module is located under the rear seat. It must've been some crash if the module itself was damaged on impact. The fault can be in several locations; it may be as simple as a connector not fully seated into one of the four distance sensors in the rear bumper. If the red light on the rear parking assist display flashes when the transmission is put in reverse, there are trouble codes stored in the module, which should lead you in the right direction. The trouble codes can be retrieved without a scan tool. There's a procedure where grounding a diagnostic connector will flash the codes at the three lights (two amber, one red) on the rear parking assist display. Get it to a technician with the proper diagnostic information, or you could get the procedure yourself with a subscription to www.alldatadiy.com. Please note there is a rear-parking-assist disable switch above the driver information center (DIC). Make sure it's on. Don't go any further without retrieving the diagnostic trouble codes.
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