GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The battery in the key fob provides power for all remote keyless functions. You can tell the battery is weak if the LED fails to illuminate or if the transmitter will not work at the normal range in any location. If you have to get close to your vehicle before the transmitter works, it is probably time to change the battery.

Conditions for Running the DTC

Vehicle battery voltage must be between 9.0-16.0 volts.

Conditions for Setting the DTC

The ISU detects low voltage from the key fob.

Action Taken When the DTC Sets

The remote function control will be diminished.

Conditions for Clearing the DTC

    •  The ISU no longer detects a low voltage condition from the key fob.
    • A history DTC will clear after 40 consecutive ignition cycles if the condition for the malfunction is no longer present.

Step

Action

Yes

No

Important: You must obtain all the keys from the vehicle owner before testing any current keys. If a key needs to be replaced, any vehicle keys not programmed during the programming procedure will be inoperative after the programming sequence is completed. Ensure that the doors, hood and trunk/rear hatch are closed prior to starting the programming procedure. If the system is placed in program mode, then the ISU will erase all previously programmed transmitters upon the receipt of the first transmitter s programming signal. Do not operate or program the transmitters in the vicinity of other vehicles that are also in the keyless entry program mode. This prevents the programming of the transmitters to the incorrect vehicle.

1

Did you perform the Keyless Entry Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Remote Keyless Entry

2

  1. Replace the battery in the suspect key fob.
  2. Test the key fob for proper operation. Refer to Keyless Entry System Description and Operation .

Did you find and correct the condition?

System OK

Go to Symptoms - Keyless Entry