B1441

DTC B1441

DTC Descriptor
DTC B1441 01
- Device Ignition Off/Run/Crank Circuit Short to Battery

DTC B1441 06
- Device Ignition Off/Run/Crank Circuit Open

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview






Typical Scan Tool Data


























Circuit/System Description

The body control module (BCM) monitors the ignition inputs ignition off/run/crank voltage, ignition 1 voltage and the accessory voltage signals supplied from the ignition switch. The ignition key resistor signal circuit provides 5-volt reference from the BCM to the ignition switch. The BCM uses the sequence that the signals appear, their voltage levels, the engine run flag (ERF) status and the remote start status to determine the power mode.

Conditions for Running the DTC

Ignition switch is in the START position.

Conditions for Setting the DTC

B1441 01

Off/run/crank voltage circuit is shorted to voltage for more than 2 seconds.

B1441 06

Off/run/crank voltage circuit is open for more than 2 seconds.

Action Taken When the DTC Sets

* 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 GMLAN 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 GMLAN serial data communications circuits.

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 of 50, without a repeat of the malfunction.

Diagnostic Aids

Use the DMM MIN/MAX function to capture/locate intermittent conditions.

Circuit/System Verification

Using a scan tool monitor the typical parameters listed above for all ignition switch positions. Compare the parameters state with the typical scan tool data above.

If all parameters are all in the normal range for all ignition switch positions and the DTC is current, replace the BCM.

Circuit/System Testing

1. With the ignition OFF, disconnect the BCM.
2. With the ignition OFF w/key out and in the ACC position, measure for 0 volts between the off/run/crank voltage circuit at the BCM connector and ground.

• If over 0 volts, disconnect the ignition switch and check the off/run/crank voltage circuit for short to voltage or short to other ignition switch signal circuit. If the circuits test normal, test or replace the ignition switch.

3. With the ignition OFF w/key in, measure for battery voltage between the off/run/crank voltage circuit at the BCM connector and ground.

• If less than battery voltage, disconnect the ignition switch and check the off/run/crank voltage circuit for an open or short to ground. If the circuits test normal, test or replace the ignition switch.

4. With the key in the RUN position, measure for less than 1 ohm between the ignition key resistor signal and the off/run/crank voltage circuits.

• If over 1 ohm, disconnect the ignition switch and check the ignition key resistor signal for an open. If the circuits test normal, test or replace the ignition switch.

5. Check the ignition key resistor signal for a short to ground or a short to voltage. If the circuits test normal, test or replace the BCM.

Component Testing

1. With the key out of ignition and with the key in ACC, measure for infinite resistance between the battery positive voltage and the off/run/crank voltage terminals of the ignition switch. Repeat the same measurement between the ignition key resistor signal and the off/run/crank voltage terminals of the ignition switch.

• If less than infinite ohms, replace the ignition switch.

2. With the key in ignition, in OFF position, measure for less than 1 ohm between the battery positive voltage and the off/run/crank voltage terminals at the ignition switch.

• If over 1 ohm, replace the ignition switch.

3. With the key in the RUN position, measure for less than 1 ohm between the ignition key resistor signal and the off/run/crank voltage terminals at the ignition switch.

• If over 1 ohm, replace the ignition switch.

4. With the key in the START position, measure for 1170-1430 ohms between the ignition key resistor signal and the ignition off/run/crank terminals at the ignition switch.

• If out of range, replace the ignition switch.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

* Programming and Relearning Programming and Relearning
* Ignition and Start Switch Replacement Verification Tests