Generic Fault Code
Free · no signupP0256
High Pressure Fuel Loop Failure
System
Fuel System
Symptom
High Pressure Fuel Loop Failure
Diagnosis & fix steps
LOGIC: Injection Pump Fuel Metering Control "B" Malfunction (Cam/Rotor/Injector).
ACTION: Review circuit wiring integrity configurations on the secondary high-pressure pump metering valve.
Red Seal field insights
Circuit Fail: Structural breakdown tracked across the secondary injection pump volume control circuit path.
Same code keeps coming back?
That's a program problem, not a part problem. Book a 30-minute uptime review with Grant, a Red Seal Heavy Duty Technician.
Read before you touch anything
- This is general reference information, not a repair manual. It is for trained, qualified technicians.
- Fault codes, meanings and procedures vary by model, serial number and software version. Confirm the code and the procedure against the manufacturer's service manual before acting.
- Follow the OEM service manual, torque specs and your site's safety procedures: lockout/tagout, block raised equipment, relieve hydraulic, fuel and air pressure, and let hot systems cool.
- You use this information at your own risk. Adventure Mechanical and AM Fleet Integrity accept no liability for damage, injury, downtime or loss arising from its use.
- Not affiliated with or endorsed by any manufacturer. Brand names are used only to identify the equipment a code applies to.
Track this across your whole fleet
This code is free to read. AM Fleet Integrity lets your team log fault codes against assets, plus the full fault-code library, QR operator reporting, PM scheduling and predictive alerts. Start free — no credit card required.
Start your free trialRelated Generic fault codes
- P0257Power Sag under Extreme Heavy Duty Operation
- P0255Erratic Engine Shuddering at Random Speeds
- P0258Fuel Rail Fails to Meet Commanded Pressure
- P0254Engine Stumbles / Hard Diesel Knock
- P0259Engine Rattles due to Uncontrolled Rail Pressure
- P0253Engine Starves for Fuel / Stalls
- P0260Random Dropouts in High-Pressure Output
- P0252Black Smoke / Engine Surges
- P0261Misfire Cylinder 1 / Lean Shake
- P0251Engine Coughs and Dies under Acceleration