Power Mode Mismatch

POWER MODE MISMATCH

CIRCUIT DESCRIPTION
Normal vehicle class 2 communications and module operations will not begin until the system power mode has been identified. Discrete wires from the ignition switch contacts are monitored by the power mode master (PMM) module in order to determine the correct power mode. The PMM communicates the system power mode to all class 2 modules on the class 2 serial data line. Refer to Body Control System Description and Operation to identify which module is the PMM and the applicable power mode look up table.

TEST DESCRIPTION

Steps 1-6:

Steps 7-14:

Step 15:

The numbers below refer to the step numbers on the diagnostic table.
7. This step tests for battery voltage on the signal circuits that are not required.
8. This step tests for no battery voltage on the required signal circuits.
9. If any ignition switch parameters that should be inactive in the present ignition switch position are active, 2 ignition switch signal circuits may be shorted together.
10. This step eliminates open circuits as the cause of the malfunction.