Error code

OBD2 P0004

OBD2P0004
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.

What it means

Fuel Volume Regulator Control Circuit High.

Severity

moderateCan drive, but may experience performance issues.

Summary

P0004 indicates a high voltage issue in the fuel volume regulator control circuit on diesel engines, typically related to the fuel volume control valve (FVCV).

Symptoms

  • Lack of power
  • No start condition

Common Causes

  • Faulty fuel volume control valve (FVCV)
  • Fault in the FVCV circuit
  • Problem with the PCM

Diagnosis

  1. Perform a visual inspection of the FVCV and connection.
  2. Test the FVCV solenoid using a current probe or multimeter.
  3. Check the circuit for power supply and PCM grounding issues.

Fixes

  • Replace faulty fuel volume control valve (FVCV).

FAQ

What should I do if my check engine light is on with code P0004?

Start by visually inspecting the FVCV and its connection, then test the solenoid for proper current draw or resistance. If issues persist, further diagnose the circuit.

Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.