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9,253 diagnostic guides

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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 8017–8040 of 8256

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U3539High Voltage System Interlock Circuit MCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3539 concerns high voltage system interlock circuit m. Learn what this fault indicates and where to begin diagnosis.U353AHigh Voltage System Interlock Circuit M PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU353A concerns high voltage system interlock circuit m performance. Learn what this fault indicates and where to begin diagnosis.U353BHigh Voltage System Interlock Circuit M LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU353B concerns high voltage system interlock circuit m low. Learn what this fault indicates and where to begin diagnosis.U353CHigh Voltage System Interlock Circuit M HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU353C concerns high voltage system interlock circuit m high. Learn what this fault indicates and where to begin diagnosis.U353DHigh Voltage System Interlock Circuit NCheck soonNetwork & Communication45–120 minutes for initial diagnosisU353D concerns high voltage system interlock circuit n. Learn what this fault indicates and where to begin diagnosis.U353EHigh Voltage System Interlock Circuit N PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU353E concerns high voltage system interlock circuit n performance. Learn what this fault indicates and where to begin diagnosis.U353FHigh Voltage System Interlock Circuit N LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU353F concerns high voltage system interlock circuit n low. Learn what this fault indicates and where to begin diagnosis.U3540High Voltage System Interlock Circuit N HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3540 concerns high voltage system interlock circuit n high. Learn what this fault indicates and where to begin diagnosis.U3541High Voltage System Interlock Circuit OCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3541 concerns high voltage system interlock circuit o. Learn what this fault indicates and where to begin diagnosis.U3542High Voltage System Interlock Circuit O PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3542 concerns high voltage system interlock circuit o performance. Learn what this fault indicates and where to begin diagnosis.U3543High Voltage System Interlock Circuit O LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3543 concerns high voltage system interlock circuit o low. Learn what this fault indicates and where to begin diagnosis.U3544High Voltage System Interlock Circuit O HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3544 concerns high voltage system interlock circuit o high. Learn what this fault indicates and where to begin diagnosis.U3545High Voltage System Interlock Circuit PCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3545 concerns high voltage system interlock circuit p. Learn what this fault indicates and where to begin diagnosis.U3546High Voltage System Interlock Circuit P PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3546 concerns high voltage system interlock circuit p performance. Learn what this fault indicates and where to begin diagnosis.U3547High Voltage System Interlock Circuit P LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3547 concerns high voltage system interlock circuit p low. Learn what this fault indicates and where to begin diagnosis.U3548High Voltage System Interlock Circuit P HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3548 concerns high voltage system interlock circuit p high. Learn what this fault indicates and where to begin diagnosis.U3549Hydrogen Tank High Pressure Sensor 1 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3549 concerns hydrogen tank high pressure sensor 1 circuit. Learn what this fault indicates and where to begin diagnosis.U354AHydrogen Tank A Temperature Sensor 1 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU354A concerns hydrogen tank a temperature sensor 1 circuit. Learn what this fault indicates and where to begin diagnosis.U354BHydrogen Tank A Temperature Sensor 2 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU354B concerns hydrogen tank a temperature sensor 2 circuit. Learn what this fault indicates and where to begin diagnosis.U354CHydrogen Tank B Temperature Sensor 1 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU354C concerns hydrogen tank b temperature sensor 1 circuit. Learn what this fault indicates and where to begin diagnosis.U354DHydrogen Tank B Temperature Sensor 2 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU354D concerns hydrogen tank b temperature sensor 2 circuit. Learn what this fault indicates and where to begin diagnosis.U354EHydrogen Tank C Temperature Sensor 1 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU354E concerns hydrogen tank c temperature sensor 1 circuit. Learn what this fault indicates and where to begin diagnosis.U354FHydrogen Tank C Temperature Sensor 2 CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU354F concerns hydrogen tank c temperature sensor 2 circuit. Learn what this fault indicates and where to begin diagnosis.U3550Hydrogen Tank A Valve Control CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3550 concerns hydrogen tank a valve control circuit. Learn what this fault indicates and where to begin diagnosis.