B3797

DTC B3797

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.

* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B3797 02

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All Door Dead Lock Circuit Short to Ground

Diagnostic Fault Information






Circuit/System Description

Door latch assemblies each contain a reversible dead lock motor, each dead lock motor is controlled by 2 circuits; the dead lock control circuit and the dead lock unlock control circuit. To dead lock a door, the body control module (BCM) locks the door by momentarily energizing the door lock security PCB relay. To complete the dead locking, the BCM momentarily applies voltage to the dead lock control circuit and ground to the door lock relay control circuit and the door latches will then dead lock.

To undead lock the door, the BCM uses the same circuit as the normal door unlocking system and the dead locks will unlatch with the rest of the door locks.

Conditions for Running the DTC

When the BCM commands the door dead lock.

Conditions for Setting the DTC

The BCM detects a short to ground in the door lock relay control circuit.

Action Taken When the DTC Sets

The dead locks will be inoperative

Conditions for Clearing the DTC

* The DTC will be current for as long as the fault is present.

* When the fault is no longer present, the DTC will be a history DTC.

* A history DTC will clear after 50 ignition cycles.

Reference Information

Schematic Reference

Door Lock/Indicator Schematics Door Lock/Indicator Schematics

Connector End View Reference

Component Connector End Views Sunshade - Left (DH6)

Description and Operation

Power Door Locks Description and Operation Description and Operation

Electrical Information Reference

* Circuit Testing Circuit Testing

* Connector Repairs Connector Repairs

* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections

* Wiring Repairs Wiring Repairs

Scan Tool Reference

Control Module References Control Module References for scan tool information

Circuit/System Verification

Command the door dead lock to LOCK with a scan tool and attempt to open the door by using the interior door handles. The interior door handles should be inoperative.

Circuit/System Testing

1. Ignition OFF, disconnect the X2 harness connector at the X50A fuseblock-underhood.

2. Connect a test lamp between the control circuit terminal 48 and ground.

3. Ignition ON, command the door dead locks to LOCK and UNLOCK with a scan tool, the test lamp should briefly illuminate when changing between the commanded states.

• If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K9 body control module

4. If all circuits test normal, replace the X50A fuseblock-underhood.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair.

* Front Compartment Fuse Block Replacement Front Compartment Fuse Block Replacement

* Control Module References Control Module References for BCM replacement, programming and setup