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Remote Keyless Entry Interference; Use of J43241 Fob Tester

Subject:Remote Keyless Entry Interference; Use Of J43241 Fob Tester

Models:1996-2007 All GM Passenger Cars and Light Duty Trucks, Vans and Utilities



The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.

Condition/Concern:

Erratic RKE operation or RKE inoperative.

Recommendation/Instructions:

As more and more electronic devices get incorporated or carried in vehicles, reports of remote keyless entry systems with poor performance or unable to program are increasing. There have been a number of identified devices that can interfere with the RKE such as cell phone cords plugged into power outlets without the phone present, wireless doorbell transmitters, garage door openers, TPM sensors, etc. If an RKE system receives two transmissions from separate sources at the same time, it will ignore both. In some cases you can locate devices transmitting unwanted signals using the RKE key fob tester, J43241. Since the unwanted transmissions are the same frequency as the key fob, the LED on the tester will light when the tester is slowly swept near the device. Be sure to sweep around all storage areas in the vehicle and under dash and seats.

Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.