P0003
UniversalThe Powertrain Control Module (PCM) detects a low voltage condition in the fuel volume regulator control circuit.
Medium SeverityThis code indicates that the Powertrain Control Module (PCM) has detected an issue with the electrical circuit controlling the fuel volume regulator, specifically a voltage that is lower than expected. This can lead to problems with fuel delivery, potentially impacting engine performance and fuel economy.
⚠️ Before You Begin (Safety First)
Working with fuel systems can be dangerous. Ensure the engine is cool and relieve fuel system pressure before disconnecting any fuel lines. Always disconnect the battery to prevent electrical shorts and unintended component activation. Fuel is highly flammable; work in a well-ventilated area away from open flames or sparks.
Common Symptoms
- Check Engine Light illuminated
- Engine may not start or may crank for a long time
- Poor engine performance (hesitation, lack of power)
- Rough idle or stalling
- Reduced fuel economy
- Engine running rich or lean
Common Causes
- Faulty fuel volume regulator (FVR) or fuel pressure regulator (FPR)
- Open or short circuit in the FVR control circuit wiring
- Corroded or loose electrical connectors
- Faulty Powertrain Control Module (PCM) (less common)
- Low voltage supply to the FVR circuit
Frequently reported on: 2010-2016 Ford F-150 (EcoBoost), 2007-2014 Chevrolet Silverado (Direct Injection models), 2010-2018 Volkswagen Golf (TDI/TSI), 2008-2015 Audi A4 (TFSI), 2007-2013 Mazda 3 (Mazdaspeed)
Diagnostic Steps
- Retrieve all diagnostic trouble codes (DTCs) using an OBD-II scanner.
- Visually inspect the wiring and connectors leading to the fuel volume regulator for signs of damage, corrosion, or loose connections.
- Using a multimeter, check for proper voltage and ground at the fuel volume regulator connector (refer to vehicle-specific wiring diagrams).
- Check for continuity in the FVR control circuit wiring between the FVR and the PCM.
- If the FVR is accessible, test its resistance against manufacturer specifications (if applicable).
- If wiring and connections are good, and voltage is low, consider replacing the fuel volume regulator.
- Clear the codes and test drive the vehicle to see if the code returns.
👨🔧 When to Call a Professional
If after initial checks you cannot identify the source of the low voltage, or if you suspect an internal fuel pump or PCM issue, it is best to consult a qualified automotive technician. Fuel system repairs require specific tools and safety precautions.
Commonly Asked Questions
What does "Fuel Volume Regulator Control Circuit Low" mean?
It means the car's computer (PCM) detected that the electrical signal to control the fuel volume regulator is receiving a lower voltage than it should.
Can I drive with a P0003 code?
It is not recommended. The issue can lead to unreliable engine operation, stalling, or loss of power, which can be dangerous.
Where is the fuel volume regulator located?
Its exact location varies by vehicle, but it's typically found on the high-pressure fuel pump or on the fuel rail itself, regulating the fuel entering the high-pressure pump.
Is this an expensive repair?
The cost can vary. If it's just a loose connection, it's cheap. If the regulator or the high-pressure fuel pump (which often integrates the regulator) needs replacement, it can be a significant expense.
Does P0003 always mean the fuel volume regulator is bad?
No, it indicates a problem with the "circuit" for the regulator. This could be faulty wiring, a bad connector, or an issue with the PCM, in addition to a failing regulator itself.