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B1422

CIRCUIT DESCRIPTION

Device Power Moding:




Normal vehicle class 2 communication will not commence until the system power mode has been identified. Four discrete wires from the ignition switch contacts are monitored by the dash integration module (DIM) in order to determine the present power mode. The DIM is the vehicle power mode master (PMM) and communicates the system power mode to all class 2 modules on the class 2 bus.

CONDITIONS FOR RUNNING THE DTC
The DIM must be powered.

CONDITIONS FOR SETTING THE DTC
One of the 4 monitored ignition switch circuits has malfunctioned.

ACTION TAKEN WHEN THE DTC SETS
The DIM implements default actions for each ignition switch position when faults are detected.

CONDITIONS FOR CLEARING THE DTC
- A current DTC clears when the malfunction is no longer present.
- A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

TEST DESCRIPTION

Steps 1-12:




Steps 15-17:




The numbers below refer to the step numbers on the diagnostic table.
7. Tests for a short to battery voltage on the active signal circuit.
8. Tests the inactive signal circuit for an open or a high resistance.
9. If any ignition switch parameters that should be inactive in the present ignition switch position are active, two ignition switch signal circuits may be shorted together.