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

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Driver Door Lock Indicator Control

1

1

1

--

Passenger Door Lock Indicator Control

1

1

1

--

Driver Door Lock Indicator Ground

--

1

--

--

Passenger Door Lock Indicator Ground

--

1

--

--

1. Door Lock Indicator Malfunction

Circuit/System Description

The driver door module (DDM) and front passenger door module (PDM) control the door lock status indicators for there respective doors. The DDM and PDM provide voltage to the indicators to illuminate when the lock system is in a virtual state of lock. The indicators only illuminate for approximately 5 seconds after lock switch activation or a door handle has been operated and the door control modules are in a virtual state of lock. When the door is open, the door lock status indicators cycle ON/OFF. The remote control door lock receiver (RCDLR) receives RFA transmissions and communicates with the door control modules for lock and unlock commands.

Reference Information

Schematic Reference

Door Lock/Indicator Schematics

Connector End View Reference

Component 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

Control Module References for scan tool information

Circuit/System Verification

Ignition ON, command the Lock Switch Indicator ON and OFF with a scan tool, the driver and passenger door lock indicators should turn ON and OFF when changing between the commanded states..

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the appropriate door lock indicator.
  2. Verify that a test lamp illuminates between B+ and the ground circuit terminal B.
  3. If the test lamp does not illuminate, test the ground circuit for an open/high resistance.
  4. Connect a test lamp between the control circuit terminal A and ground.
  5. Ignition ON, command the Lock Switch Indicator ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
  6. If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the door module.
    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 door module.
  7. If all circuits tests normal, replace the door lock indicator.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Door Lock Status Indicator Replacement
    •  Control Module References for DDM or PDM replacement, setup and programming