B1374

CIRCUIT DESCRIPTION
The BCM uses a input from the ignition switch to determine the power mode that the vehicle is in, this input is ignition 1. When the BCM senses that ignition 1 is inactive when ignition 0 and 3 are active and the engine is running, DTC B1374 is set.

CONDITIONS FOR RUNNING THE DTC
^ The engine is running.
^ At least 20 seconds has elapsed since the engine was started.

CONDITIONS FOR SETTING THE DTC
The ignition 1 input is inactive after the engine has been running for 20 seconds.

ACTION TAKEN WHEN THE DTC SETS
^ The SERVICE VEHICLE SOON indicator illuminates.
^ The check gages chime sounds.

CONDITIONS FOR CLEARING THE DTC
^ A current DTC B1374 will clear when the code setting condition is no longer present and the ignition switch is cycled.
^ A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

DIAGNOSTIC AIDS
If the DTC is a history DTC, the problem may be intermittent. Perform the tests shown while wiggling the wiring and connectors. This can often cause the malfunction to appear.

TEST DESCRIPTION

Steps 1-7:

Steps 8-12:

4. This step determines if the ignition 1 circuit is shorted to ground.
5. This step determines if the BCM is internally shorted.
6. This step determines if voltage is supplied from the battery to the fuse.