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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

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All severities9253 Low priority305 Check soon8256 Urgent621

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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 1153–1176 of 1939

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P2334Ignition Coil L Primary Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2334 relates to ignition coil l primary control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2335Ignition Coil L Secondary CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2335 relates to ignition coil l secondary circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2374Turbocharger/Supercharger Inlet Pressure Sensor B CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2374 relates to turbocharger/supercharger inlet pressure sensor b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2375Turbocharger/Supercharger Inlet Pressure Sensor B Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2375 relates to turbocharger/supercharger inlet pressure sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2376Turbocharger/Supercharger Inlet Pressure Sensor B Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2376 relates to turbocharger/supercharger inlet pressure sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2377Turbocharger/Supercharger Inlet Pressure Sensor B Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2377 relates to turbocharger/supercharger inlet pressure sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2378Turbocharger/Supercharger Inlet Pressure Sensor B Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2378 relates to turbocharger/supercharger inlet pressure sensor b circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P2379O2 Sensor Out of Range During Deceleration Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2379 relates to o2 sensor out of range during deceleration bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P237AO2 Sensor Exhaust Sample Error Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP237A relates to o2 sensor exhaust sample error bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P237BO2 Sensor Exhaust Sample Error Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP237B relates to o2 sensor exhaust sample error bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P237CExhaust Heat Exchanger Exhaust Bypass Valve A Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP237C relates to exhaust heat exchanger exhaust bypass valve a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P237DExhaust Heat Exchanger Exhaust Bypass Valve A Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP237D relates to exhaust heat exchanger exhaust bypass valve a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P237EExhaust Heat Exchanger Exhaust Bypass Valve A Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP237E relates to exhaust heat exchanger exhaust bypass valve a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P237FExhaust Heat Exchanger Exhaust Bypass Valve A Control PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP237F relates to exhaust heat exchanger exhaust bypass valve a control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2390Diesel Intake Air Flow B Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2390 relates to diesel intake air flow b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2391Diesel Intake Air Flow B Control PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2391 relates to diesel intake air flow b control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2392Diesel Intake Air Flow B Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2392 relates to diesel intake air flow b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2393Diesel Intake Air Flow B Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2393 relates to diesel intake air flow b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2394Diesel Intake Air Flow B Control Stuck OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2394 relates to diesel intake air flow b control stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2395Diesel Intake Air Flow B Control Stuck ClosedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2395 relates to diesel intake air flow b control stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2396Diesel Intake Air Flow B Position Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2396 relates to diesel intake air flow b position sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2397Diesel Intake Air Flow B Position Sensor Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2397 relates to diesel intake air flow b position sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2398Diesel Intake Air Flow B Position Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2398 relates to diesel intake air flow b position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2399Diesel Intake Air Flow B Position Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2399 relates to diesel intake air flow b position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.