Input/Output Diagnostic Mode
After the BCM reads all of the DTCs in the memory, the BCM enters the Input/Output Diagnostic Mode.
The BCM flashes the fasten seat belts indicator and sounds the chime once when any of the following inputs are activated:
- Courtesy lamp switches
- Door lock cylinder switches
- Driver door ajar switch
- Headlamp switch
- Instrument panel (I/P) compartment lamp switch
- Keyless entry request for door lock/unlock
- Keyless entry request for the alarm (RPO UA6)
- Passenger door ajar switch
- Power door lock switches
- Liftgate ajar switch
- Sliding door ajar switches
- Shock sensor
- Hazard switch
Perform the following procedure in order to test the BCM outputs:
- Ensure that the BCM is in the diagnostic mode. Refer to Entering On-Board Diagnostic Mode.
- Cycle the interior light switch ON then OFF.
- The BCM will enter the Output Diagnostic Test Mode 1.
- Each cycle of the interior light switch ON/OFF will select from following test modes depending on BCM type:
- Test Mode 1-De-activates the courtesy lights output and removes power to all of the interior lamps.
- Test Mode 2-Activates the courtesy lights output and provides power to all of the interior lamps. Interior lamp override switch must be ON.
- Test Mode 3-Activates the courtesy lights output and turns ON all of the courtesy lamps. Interior lamp switch must be ON.
- Test Mode 4-Activates the theft deterrent relay for 1 second and turns ON the headlamps. BCM type 4 only.
- Test Mode 5-Energizes the horn relay for 25 ms. BCM type 4 only.
- Test Mode 6-Turns on the security LED indicator. BCM type 4 only.
- Test Mode 7-Turns off the security LED indicator. BCM type 4 only.
When the BCM completes all test modes, the BCM will repeat the test mode sequence.