Circuit/System Testing
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2012 GMC Yukon XL, 2012 GMC Yukon, 2012 Chevrolet Tahoe, 2012 Chevrolet Suburban, and 2012 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
- Ignition OFF, disconnect the harness connector at the GDO.
- Ignition OFF, test for less than 10 Ω between the ground circuit terminal 3 and ground.
- If greater than the specified range, test the ground circuit for an open/high resistance.
- Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 1 and ground.
- If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
- Ignition ON, hold the two outer buttons on the GDO for 30 seconds. After 20 seconds, the LEDs will flash indicating that all learned transmitter values have been cleared. After an additional 10 seconds, the LEDs will flash again indicating it has entered the diagnostic mode. Place the J 41540
universal home remote tester near the GDO and individually press each button of the GDO. The tester should indicate when each button is pressed.
- If one or more of the buttons does not respond when each button is pressed, replace the GDO.
- Instruct the customer to program the GDO. Refer to the vehicle owners service information. A possible rolling code or incompatibility with the GDO receiver will prevent programming.
NOTE:
This step will clear any learned transmitters from the GDO. This will require reprogramming by the customer to reestablish GDO functionality.