GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptor

DTC B1349: Device Ground 1 Circuit Open

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Door Lock Switch Signal

B3270 or B3272

1, 2, 3

1, 2, 3

--

Driver Door Lock Actuator Unlock Control

2

2

2

--

Door Lock Actuator Unlock Control

3

3

3

--

Door Lock Actuator Lock Control

1

1

1

--

Door Lock Switch Ground

--

1, 2, 3

1, 2, 3

--

Center Console Fuse Block Ground

--

B1349

1, 2, 3

--

1. Door Locks Inoperative

2. Driver Door Unlock Inoperative

3. Door Unlock Inoperative

Circuit/System Description

The body control module (BCM) door locks ground circuit 550 provides ground for the door lock actuator lock and unlock controls in the BCM that control the door latch assemblies. If the BCM detects an open in this circuit, DTC B1349 is set.

Conditions for Running the DTC

Battery voltage must be between 9-16 volts.

Conditions for Setting the DTC

    • The BCM detects the door locks ground circuit 550 open.
    • The conditions above must be present for more than 0.3 second.

Action Taken When the DTC Sets

    • The BCM stores the DTC to memory.
    • The door lock actuators will not lock or unlock.

Conditions for Clearing the DTC

    • This DTC will change from current to history when the fault is no longer present.
    • A history DTC will clear after 100 consecutive ignition cycles if the condition for the malfunction is no longer present.
    • The technician issues a scan tool CLEAR DTCs command.

Reference Information

Schematic Reference

Door Lock/Indicator Schematics

Connector End View Reference

    •  Vehicle Access Connector End Views
    •  Data Communication Connector End Views

Description and Operation

Power Door Locks Description and Operation

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions
    •  Scan Tool Output Controls

Circuit/System Verification

Ignition ON, observe the scan tool Door Lock Switch parameters while pressing both the door lock and door unlock switches. The reading should change between ON and OFF.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector C2 at the BCM.
  2. Test for less than 1 ohm of resistance between the ground circuit terminal C2 and ground.
  3. If greater than the specified range, test the ground circuit for an open/high resistance, if circuit tests normal, replace the BCM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for BCM replacement, setup, and programming