B1422

CIRCUIT DESCRIPTION
The Body Control Module (BCM) monitors the IGNO, IGN1 and the CRANK circuits from the ignition switch. The BCM uses the voltage state (B+ or 0) and the sequence of state changes to determine the power mode called for by the ignition switch.

CONDITIONS FOR RUNNING THE DTC
The BCM must be powered and must detect a change in the ignition switch circuit states.

CONDITIONS FOR SETTING THE DTC
^ The BCM detects an improper voltage on one of the ignition switch circuits.
^ One of the ignition switch circuits may be shorted to either B+ or ground.
^ The sequence of the change of the circuit may be incorrect for the expected power mode.

ACTION TAKEN WHEN THE DTC SETS
^ The BCM stores the DTC to memory.
^ The BCM operates in a fail-safe power mode dependent on the last valid power mode detected and the state of the engine run flag data on the class 2 serial data communications circuits.
^ The other modules on the vehicle operate in a fail safe power mode dependent on the last valid power mode transmitted by the BCM and the state of the engine run flag on the class 2 serial data communications circuits.

CONDITIONS FOR CLEARING THE DTC
^ The current DTC will clear when the BCM detects a sequence of ignition switch inputs that match the expected power mode.
^ A history DTC will clear after 100 ignition switch ON/OFF cycles with no repeated malfunction.

TEST

Steps 1-4:

Steps 5-15: