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

I/P Fuse Block B+

2

2

--

--

Fuel Door Release Actuator Lock Control

2

1

2

--

Fuel Door Release Actuator Unlock Control

2

1

2

--

Relay Ground

--

2

2

--

1. Fuel Door Release Actuator Inoperative

2. Fuel Door Release Actuator and Door Latches Inoperative

Circuit/System Description

The fuel door release actuator shares the circuit with the driver door latch. The body control module (BCM), upon receipt of a lock switch lock or unlock signal, will switch the appropriate door latch, as well as a fuel filler door release actuator control circuits to battery positive voltage. The opposing side of the door latch and fuel filler door release actuator is connected to ground provided by the I/P fuse block through the other the door latch control circuits, along with the fuel filler door release actuator, will lock or unlock as commanded.

Reference Information

Schematic Reference

Door Lock/Indicator Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Fuel Fill Door 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

Observe the operation of the power door locks while using the door lock switch. All doors and the fuel filler door should perform the LOCK and UNLOCK function.

If any door does not function as commanded, refer to Power Door Locks Malfunction.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the fuel door release actuator.
  2. Test for less than 1 ohm between the control circuit terminal 1 and ground.
  3. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance.
  4. Test for less than 1 ohm between the control circuit terminal 2 and ground.
  5. If greater than the specified range, test the control circuit for a short to voltage or an open/high resistance.
  6. Connect a test lamp between the control circuit terminal 1 and control circuit terminal 2.
  7. Ignition ON, command the doors to LOCK and UNLOCK by using the door lock switch. The test lamp should illuminate while commanding the LOCK and UNLOCK states.
  8. If the test lamp remains OFF during either command, test either control circuit for a short to ground.
  9. If all circuits test normal, test or replace the fuel door release actuator.

Component Testing

  1. Ignition OFF, disconnect the harness connector at the fuel door release actuator
  2. Install a 15A fused jumper wire between the control terminal 1 and 12V. Momentarily install a jumper wire between the control terminal 2 and ground. The fuel door release actuator should perform the LOCK/UNLOCK function.
  3. If the function does not perform as specified, replace the fuel door release actuator.
  4. Reverse the jumper wires. The fuel door release actuator should perform the UNLOCK/LOCK function.
  5. If the function does not perform as specified, replace the fuel door release actuator.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Fuel Tank Filler Door Lock Actuator Replacement