Volt

DTC P04C8, P04CA, or P04CB

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.

The hybrid powertrain control module 2 is awake

P04C8 00

The hybrid powertrain control module 2 the fuel fill door open request switch circuit voltage is mid-range between expected high and low voltage values.

P04CA 00

The hybrid powertrain control module 2 detects a short to ground in the refuel request signal circuit.

P04CB 00

The hybrid powertrain control module 2 detects a short to voltage or an open/high resistance in the refuel request signal circuit.

The refuel request switch will still function normally.

DTC P04C8 00, P04CA 00 and P04CB 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 filler door to UNLOCK by pressing the S117 refuel request switch, the M97 fuel door lock actuator should UNLOCK allowing the fuel filler door to open.

1. Vehicle OFF, disconnect the harness connector at the S117 refuel request switch.
2. Test for less than 70 Ω between the low reference circuit terminal 6 and ground.

⇒	If greater than the specified range, test the low reference circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.

3. Vehicle in Service Mode, test for 4.75 -- 5.25 V between the signal circuit terminal 3 and ground.

⇒	If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.

⇒	If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.

4. If all circuits test normal, test or replace the S117 refuel request switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.