B1441

DTC B1441, B1442, or B1443

Circuit Description

The body control module (BCM) monitors the ignition inputs Ignition Off/Run/Crank, Ignition 1 Run/Crank and the Ignition Accessory signals supplied from the ignition switch. The BCM uses the sequence that the signals appear, their voltage levels and the engine run flag (ERF) status to determine the power mode. Battery voltage is supplied to the ignition switch by the IGN TRANSD fuse. The ignition key resistor signal from the BCM provides a 5-volt supply voltage to the ignition switch. The following table shows the correct ignition switch signals.





DTC Descriptors

This diagnostic procedure supports the following DTCs.

* DTC B1442 Device Ignition OFF, RUN, and CRANK Circuit Open
* DTC B1443 Device Ignition OFF, RUN, and CRANK Circuit High

Conditions for Running the DTC

Battery positive voltage is 9-16 volts.

Conditions for Setting the DTC

DTC B1442

The BCM detects that the Off/Run/Crank signal is open for at least 1 second.

DTC B1443

The BCM detects that the Off/Run/Crank signal is shorted to voltage for at least 1 second.

Action Taken When the DTC Sets

* The BCM stores DTC B1442 or B1443 in memory.
* The BCM determines a fail-safe power mode dependent on the last valid power mode detected and the state of the ERF.

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

Step 1 - Step 8:

Step 9 - Step 16:

The number below refer to the step number on the diagnostic table.
3. The correct reading on this step should be B+, but the parameter was scaled to maximum 5 volts, to increase reading accuracy in the lower range.