B1440

DTC B1440

Circuit Description
The body control module (BCM) is the power mode master responsible for sending ignition switch position information on the class 2 serial data link. The BCM monitors 3 discrete wires from the ignition switch contacts and the engine run flag (ERF) in order to determine the present power mode. The BCM communicates this power mode information to all class 2 modules on the class 2 serial data link. The following table represents correct BCM power mode data:

Correct Ignition Switch Inputs:

Correct Ignition Switch Inputs

Conditions for Running the DTC
The only requirements are voltage and ground.

Conditions for Setting the DTC
One of the 3 monitored ignition switch circuits has malfunctioned. The DTC will set, if one of the following situations is present:

Incorrect Ignition Switch Inputs Part 1:

Incorrect Ignition Switch Inputs Part 2:

Incorrect Ignition Switch Inputs

Action Taken When the DTC Sets
The BCM 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.

Step 1 - 2:

Step 3 - 7:

Step 8 - 14:

Step 15: