Your vehicle is equipped with essential systems that work together to keep your vehicle running as it should. The automotive fuel system, for example, is made up of several components. One of the crucial components of this system is a fuel pump.
It is sometimes unavoidable for engine components such as your fuel pump to fail. Thankfully, modern vehicles are equipped with on-board diagnostic (OBD) systems that usually alert you if something goes wrong with your engine components.
P0003 is a generic diagnostic trouble code related to the operation of the high-pressure fuel pump found on certain vehicles.
What Does the P0003 Code Mean?
Diagnostic trouble code (DTC) P0003 stands for “Fuel Volume Regulator Control Circuit Low.” Although rare, it’s not impossible for your scan tool to retrieve this code. The P0003 code is commonly seen on common rail diesel (CRD) engines, and gasoline direct injection (GDI) equipped vehicles.
Code P0003 simply means that your powertrain control module (PCM) has detected that your fuel volume regulator’s voltage readings are below the normal range.
Note: Although P0003 is a generic code, its definition may vary depending on the vehicle manufacturer. We recommend checking a repair manual or repair database for the exact code definition.
More About Fuel Volume Regulators
The role of a fuel volume regulator (also known as a fuel volume control valve) is to regulate the amount of fuel entering the high-pressure pump. An automotive fuel system is composed of several components such as the fuel tank, fuel injector, lines, and filters. High-pressure fuel systems are equipped with a high-pressure fuel pump.
The role of a high-pressure fuel pump is to increase fuel pressure at the fuel rail. This pressure is necessary for your fuel injectors to work as they should. CRD and GDI fuel systems have a low and high-pressure side. The fuel volume regulator is the part responsible for controlling the pressure to the high-pressure fuel pump.
P0003 is set when the PCM detects that the fuel volume regulator circuit voltage is below the specified limit for the current operating state.
What are the Possible Causes of the P0003 Code?
P0003 is a generic code. However, the triggers of this code may vary depending on the type of vehicle you own. Here are some of the possible causes of this code:
- Malfunctioning fuel volume regulator
- Electrical wiring/ harness issue in your fuel volume regulator
- PCM failure
- Blown #74 fuse (common on Power Stroke engines)
What are the Common Symptoms of the P0003 Code?
Here are the common symptoms related to the P0003 code:
- Check Engine Light
- Difficulty starting your vehicle
- “Limp mode” may be enabled
- Lack of engine power
- Decreased fuel economy
- Decreased engine performance
- Vehicle won’t start
How to Diagnose the P0003 Code
Diagnosing the P0003 trouble code can be tricky. If you’re not well-versed with auto repair, it is best to bring your vehicle to an auto repair shop and have the problem diagnosed by a mechanic.
If you really want to diagnose this code yourself, here’s a video to help you understand this code better:
How to Fix the P0003 Code
P0003 is a generic trouble code that may appear in various makes and models. However, diagnostic and repair procedures may vary depending on the specific vehicle you own. For example, repair procedures for P0003 in a Ford may be different from a P0003 code in a Chevy.
Again, if you’re not equipped with the DIY auto repair skills, it is best to leave the job to a professional. However, if you’re determined to fix this code yourself, you can use online auto repair sources and guides to help you identify the repair steps that are compatible with your vehicle. To help you with your car repair, you may also get an ALLDATA single-vehicle subscription.