Volt

DTC P04BB, P04BC, or P04C0

The hybrid powertrain control module 2 monitors the voltage values of the fuel fill door open request wake-up signal circuit and the fuel door request signal circuit. When the refuel request switch is pressed, the two switch contacts close. This provide B+ to the Wake-up Circuit input of the hybrid powertrain control module 2 and lowers the voltage on the fuel door request signal circuit input to the hybrid powertrain control module 2. The hybrid powertrain control module 2 detects the voltage on the signal circuits and commands the fuel system to vent and sends a serial data message to the driver information centre to display the Wait to Refuel message. The hybrid powertrain control module 2 then energises the fuel door lock/unlock actuator to unlock the fuel door.

Hybrid Powertrain Control Module 2 is awake

P04BB 00

The hybrid powertrain control module 2 has detected a short to ground, short to voltage or an open/high resistance on either of the lock actuator control circuits

P04BC 00

The hybrid powertrain control module 2 provided a lock command with no correspoding lock status indication on the fuel door lock actuator input circuit

P04C0 00

The hybrid powertrain control module 2 provided an unlock command with no correspoding unlock status indication on the fuel door lock actuator input circuit

DTC P04BB 00, P04BC 00 and P04C0 00 are type B DTCs

Schematic Reference

Release Systems Schematics : Tailgate Schematics → Release System Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Fuel Fill Door Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Vehicle in Service Mode command the fuel door to LOCK and UNLOCK with a scan tool, the M97 fuel door lock actuator should perform the LOCK and UNLOCK functions.

1. Vehicle OFF, disconnect the harness connector at the M97 fuel door lock actuator.
2. Vehicle in Service Mode, verify that a test lamp illuminates between the control circuit terminal 1 and ground.

⇒	If the test lamp is OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.

3. Verify that a test lamp illuminates between the control circuit terminal 2 and ground.

⇒	If the test lamp is OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.

4. Connect a test lamp between the control circuit terminal 1 and the control circuit terminal 2
5. Vehicle in Service Mode, command the fuel door to LOCK and UNLOCK with a scan tool. The test lamp should briefly illuminate while changing between the commanded states.

⇒	If the test lamp is always OFF, test both control circuits for a short to voltage. If the circuits test normal, replace the K114B hybrid powertrain control module 2.

6. If all circuits test normal, test or replace the M97 fuel door lock actuator.

Fuel Door Lock Actuator

1. Vehicle OFF, disconnect the harness connector at the M97 fuel door lock actuator.
2. Install a 25 A fused jumper wire between one of the control terminals and 12 V. Momentarily install a jumper wire between the other control terminal and ground. Reverse the jumper wires at least two times, the M97 fuel door lock actuator should perform the LOCK and UNLOCK functions.

⇒	If it does not perform as specified, replace the M97 fuel door lock actuator.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.