Cummins Fault Code
Free · no signupP00AF
Severe Derate
System
Turbo
Symptom
Severe Derate
Diagnosis & fix steps
LOGIC: VGT Actuator Position Error.
ACTION: Check for a stuck VGT linkage or failed electronic actuator.
Red Seal field insights
Logic: The ECM cannot move the turbo vanes to the commanded position. Common on ISX/X15.
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.
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Start your free trialRelated Cummins fault codes
- Cummins 112/113/114 (635)Turbo Lag / Low Boost.
- 5177Severe Derate / VGT Frozen
- P0251Engine Cuts Out under Load / Misfire
- P000FSudden Engine Shutdown
- P0252Engine Surges under Load / Cuts Out
- FC 441ECM may lose communication; engine stumbles or display flickers.
- SPN 100 FMI 1Engine Shutdown
- FC 234Engine speed has exceeded the safety threshold. Possible fuel system fault.
- SPN 100 FMI 2Stop Engine Light
- FC 1922Filter light flashes. If ignored, engine will severely derate and eventually "Lock Out."