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Makes 🢒 Cadillac 🢒 2009 🢒 CTS 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Fuel Filler Door Release Inoperative

Fuel Filler Door Release Inoperative European

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

FUEL/DR/RELSE Relay Coil B+

1

1

1

--

FUEL/DR/RELSE Relay Switch B+

1

1

1

--

Fuel Door Actuator Control

1

1

1

--

Spare Relay Coil Control

1

1

1

--

FUEL/DR/RELSE Relay Ground

--

1

--

--

1. Fuel Door Release Malfunction

Circuit/System Description

The FUEL/DR/RELSE relay switch and relay coil is supplied with B+ at all times via the DR/LCK fuse. The locking and unlocking of the fuel door is a function of the power door lock system. When the vehicles doors are unlocked, the body control module (BCM) will respond by applying voltage to the FUEL/DR/RELSE relay coil control circuit. This energizes the coil causing the switch contacts to close. With the switch contacts closed, B+ is supplied to the fuel door release actuator, unlocking the fuel door.

Reference Information

Schematic Reference

Release Systems 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 power door lock switch. All doors should LOCK and UNLOCK as commanded.

⇒If the power door locks do not lock and unlock, refer to Power Door Latch System Malfunction.

Circuit/System Testing
  1. Ignition OFF, disconnect the FUEL/DR/RELSE relay.
  2. Test for less than 10 ohms between the ground circuit terminal 87A and ground.
    3. ⇒If greater than the specified range, test the ground circuit for an open/high resistance.
  3. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 87 and ground.
    4. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  4. Verify a test lamp illuminates between the B+ circuit terminal 86 and ground.
    5. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  5. Connect a test lamp between the control circuit terminal 85 and ground.
  6. Command the power door locks to LOCK and UNLOCK using the power door lock switch. The test lamp should turn ON and OFF when changing between the commanded states.
    7. ⇒If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the BCM.
    ⇒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 BCM.
  7. Ignition OFF, connect the FUEL/DR/RELSE relay. Disconnect the harness connector at the fuel door release actuator.
  8. Test for less than 10 ohms between the control circuit terminal 2 and ground.
    9. ⇒If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the FUEL/DR/RELSE relay.
  9. Test for less than 10 ohms between the control circuit terminal 1 and ground.
    10. ⇒If greater than the specified range, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the LCK relay.
  10. Connect a test lamp between the control circuit terminal 2 and ground.
  11. Command the power door locks to UNLOCK using the power door lock switch. The test lamp should illuminate while commanding the UNLOCK function.
    12. ⇒If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the FUEL/DR/RELSE relay.
  12. Connect a test lamp between the control circuit terminal 1 and ground.
  13. Command the power door locks to LOCK using the power door lock switch. The test lamp should illuminate when commanding the LOCK function..
    14. ⇒If the test lamp does not illuminate, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the LCK relay.
  14. If all circuits test normal, test or replace the fuel door release actuator.

Component Testing

Relay Test

  1. Ignition OFF, disconnect the appropriate relay.
  2. Test for 60-180 ohms between terminals 85 and 86.
    3. ⇒If not within the specified range, replace the relay.
  3. Test for infinite resistance between the following terminals:
    4. • 30 and 86
    • 30 and 87
    • 30 and 85
    • 85 and 87
    ⇒If not the specified value, replace the relay.
  4. Install a 25-amp fused jumper wire between relay terminal 85 and 12 volts. Install a jumper wire between relay terminal 86 and ground. Test for less than 2 ohms between terminals 30 and 87.
    5. ⇒If greater than the specified range, replace the relay.

Important: When performing the following tests, make sure that the device is not all ready in the position the test is attempting to produce.

Fuel Door Release Actuator

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

    •  Relay Replacement
    •  Control Module References for BCM replacement, setup, and programming