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Find codes by symptomChoose what you notice to search matching code guides.

Rough idle or shakingVibration while stopped Hard to startLong cranking or no-start Engine stallsCuts out at idle or on the road Hesitates or loses powerSlow response when accelerating Battery light is onCharging system warning Harsh gear changesDelayed or rough shifting

A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

FiltersSeverity · family

Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.

Diagnostic codes

Showing 8041–8064 of 8256

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U3551Hydrogen Tank A Valve Enable CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3551 concerns hydrogen tank a valve enable circuit. Learn what this fault indicates and where to begin diagnosis.U3552Hydrogen Tank A Valve PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3552 concerns hydrogen tank a valve performance. Learn what this fault indicates and where to begin diagnosis.U3553Hydrogen Tank B Valve Control CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3553 concerns hydrogen tank b valve control circuit. Learn what this fault indicates and where to begin diagnosis.U3554Hydrogen Tank B Valve Enable CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3554 concerns hydrogen tank b valve enable circuit. Learn what this fault indicates and where to begin diagnosis.U3555Hydrogen Tank B Valve PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3555 concerns hydrogen tank b valve performance. Learn what this fault indicates and where to begin diagnosis.U3556Hydrogen Tank C Valve Control CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3556 concerns hydrogen tank c valve control circuit. Learn what this fault indicates and where to begin diagnosis.U3557Hydrogen Tank C Valve Enable CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3557 concerns hydrogen tank c valve enable circuit. Learn what this fault indicates and where to begin diagnosis.U3558Hydrogen Tank C ValveCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3558 concerns hydrogen tank c valve. Learn what this fault indicates and where to begin diagnosis.U3559Air Inlet Pressure Sensor CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3559 concerns air inlet pressure sensor circuit. Learn what this fault indicates and where to begin diagnosis.U355ACharge Air Cooler Outlet Pressure Sensor 1 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU355A concerns charge air cooler outlet pressure sensor 1 circuit. Learn what this fault indicates and where to begin diagnosis.U355BCharge Air Cooler Outlet Pressure Sensor 2 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU355B concerns charge air cooler outlet pressure sensor 2 circuit. Learn what this fault indicates and where to begin diagnosis.U355CCharge Air Cooler Outlet Temperature Sensor CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU355C concerns charge air cooler outlet temperature sensor circuit. Learn what this fault indicates and where to begin diagnosis.U355DExpander Inlet Pressure Sensor 1 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU355D concerns expander inlet pressure sensor 1 circuit. Learn what this fault indicates and where to begin diagnosis.U355EExpander Inlet Pressure Sensor 2 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU355E concerns expander inlet pressure sensor 2 circuit. Learn what this fault indicates and where to begin diagnosis.U355FCathode Backpressure Valve Control CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU355F concerns cathode backpressure valve control circuit. Learn what this fault indicates and where to begin diagnosis.U3560Cathode Backpressure Valve Position Sensor CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3560 concerns cathode backpressure valve position sensor circuit. Learn what this fault indicates and where to begin diagnosis.U3561Cathode Bypass Valve Control CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3561 concerns cathode bypass valve control circuit. Learn what this fault indicates and where to begin diagnosis.U3562Cathode Bypass ValveCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3562 concerns cathode bypass valve. Learn what this fault indicates and where to begin diagnosis.U3563Cathode Bypass Valve Position Sensor CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3563 concerns cathode bypass valve position sensor circuit. Learn what this fault indicates and where to begin diagnosis.U3564Hydrogen Supply Line A Pressure Sensor 1 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3564 concerns hydrogen supply line a pressure sensor 1 circuit. Learn what this fault indicates and where to begin diagnosis.U3565Hydrogen Supply Line A Pressure Sensor 2 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3565 concerns hydrogen supply line a pressure sensor 2 circuit. Learn what this fault indicates and where to begin diagnosis.U3566Anode Inlet Pressure Sensor 1 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3566 concerns anode inlet pressure sensor 1 circuit. Learn what this fault indicates and where to begin diagnosis.U3567Anode Inlet Pressure Sensor 2 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3567 concerns anode inlet pressure sensor 2 circuit. Learn what this fault indicates and where to begin diagnosis.U3568Anode Multifunction Valve Control CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3568 concerns anode multifunction valve control circuit. Learn what this fault indicates and where to begin diagnosis.