Problem code definition P0003
The P0003 code is associated with an electrical circuit that connects to the fuel pressure regulator.

It can also refer to other codes, such as: P0001, P0002 or P0004.

Which means the appearance of the P0003 code

P0003 is not a very common malfunction code and is more common on diesel engines with Common Rail (CRD) and / or diesel engines as well as on vehicles with direct gasoline injection (GDI).

P0003 is a general OBD-II code that indicates a problem with the engine control module (ECM) reading the signals from the fuel pressure regulator on the engine’s fuel injection rail.

The ECM regulates the fuel pressure of the fuel pump, receiving information about the actual fuel pressure through this circuit. When the computer detects a pressure that does not fall within the permissible fuel pump pressure range, it sets the engine failure indicator. The code will save fuel and may damage the engine. On the other hand, this code is rare.

What causes the P0003 code?
The low fuel volume regulator control circuit code can have several causes:

• Fuel Volume Regulator Solenoid (FVR) Failure
• Cabling / FVR wiring problem (short circuit, corrosion, etc.)
• Plug disconnected for the fuel regulator
• Possible corrosion in the sensor connector.
• Sensor wiring to ECM damaged
• Leakage from the fuel pressure regulator or damage.
• Fuel pump defective
• ECM is damaged.
• Fuel pressure regulator defective

What are the symptoms of P0003 code?

Code P0003 will display the indicator on the dashboard / engine control panel and may be affected by:

• Malfunction indicator light (MIL)
• The vehicle won’t start
• “Stall mode” on and / or no power
• Reduced engine performance while driving
• It is possible to stop while driving
• May cause exhaust gases to be black or white.
• Damage to the catalyst in the exhaust system