P2370 — Fuel Volume Regulator B Control Circuit Open
An open circuit is detected on the control line for the second fuel volume regulator (B) used on twin high-pressure-pump diesel systems. Without this regulator the high-pressure pump cannot meter fuel for its assigned cylinder bank, leading to rail-pressure faults and limp-home behaviour.
General code reference. Confirm the definition and diagnostic procedure for your vehicle's year, model and engine. A stored code alone does not identify a failed part.
Affected components
- Fuel volume regulator b
- High pressure pump b
- Fuel rail
Possible causes to check
These are possible checks, not a ranked diagnosis. Follow the vehicle manufacturer's test procedure before replacing parts.
- Open in harness or connector to regulator B
- Regulator solenoid winding open
- Pin pushed back out of connector body
Diagnostic notes
- The malfunction indicator lamp may illuminate
- This code can affect emissions
Sources
Check each reference's vehicle and model-year scope. General background links do not establish which fault is most likely on your vehicle.
Diagnostic information is provided for reference only. Confirm the code with a compatible scan tool and follow the vehicle manufacturer's service procedures before replacing components.