P0001 - Fuel Volume Regulator Control Circuit Open
A fuel volume regulator can be used to control the volume of fuel that a pump delivers.
On high pressure fuel systems the fuel volume regulator can be used to control the amount of fuel going from the low pressure system into the high pressure pump. By regulating the amount of fuel entering the high pressure pump the pressure can be controlled, there are a number of benefits of using this method of control:
- The HP pump is not being over worked and putting a load on the engine when it is not required.
- Fuel return temperatures are lower
The methods of fuel volume regulation will vary depending on the type of fuel system fitted to the vehicle.
Fault Code Explained
Although this fault code indicates that the fuel volume regulator circuit is open, this does not always mean a complete break in the circuit.
The fault code can also be set for the following reasons:
- A power supply issue (no supply Voltage)
- A faulty component
Due to the number of different types of fuel systems and methods used to control fuel volume, it is recommended to refer to the manufacturers fault finding information for a detailed test plan on diagnosing this fault code.
Some manufacturers may use this fault code in relation to a fuel pressure control system.