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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 241–264 of 987

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P050CCold Start Engine Coolant Temperature PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP050C relates to cold start engine coolant temperature performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0511Idle Air Control CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP0511 indicates a fault related to idle air control circuit. Learn the likely causes and a practical diagnostic order before replacing parts.P0526Fan Speed Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP0526 relates to fan speed sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0527Fan Speed Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0527 relates to fan speed sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0528Fan Speed Sensor Circuit No SignalCheck soonEngine Problems30–120 minutes for initial diagnosisP0528 relates to fan speed sensor circuit no signal. Check the fault conditions and vehicle-specific procedure before replacing parts.P0529Fan Speed Sensor Circuit IntermittentCheck soonEngine Problems30–120 minutes for initial diagnosisP0529 relates to fan speed sensor circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P052ACold Start A Camshaft Position Timing Over-Advanced Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP052A relates to cold start a camshaft position timing over-advanced bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P052BCold Start A Camshaft Position Timing Over-Retarded Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP052B relates to cold start a camshaft position timing over-retarded bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P052CCold Start A Camshaft Position Timing Over-Advanced Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP052C relates to cold start a camshaft position timing over-advanced bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P052DCold Start A Camshaft Position Timing Over-Retarded Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP052D relates to cold start a camshaft position timing over-retarded bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P054ACold Start B Camshaft Position Timing Over-Advanced Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP054A relates to cold start b camshaft position timing over-advanced bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P054BCold Start B Camshaft Position Timing Over-Retarded Bank 1Check soonEngine Problems30–120 minutes for initial diagnosisP054B relates to cold start b camshaft position timing over-retarded bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P054CCold Start B Camshaft Position Timing Over-Advanced Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP054C relates to cold start b camshaft position timing over-advanced bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P054DCold Start B Camshaft Position Timing Over-Retarded Bank 2Check soonEngine Problems30–120 minutes for initial diagnosisP054D relates to cold start b camshaft position timing over-retarded bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P055AEngine Oil Pressure Sensor/Switch B CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP055A relates to engine oil pressure sensor/switch b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P055BEngine Oil Pressure Sensor/Switch B Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP055B relates to engine oil pressure sensor/switch b range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P055CEngine Oil Pressure Sensor/Switch B LowCheck soonEngine Problems30–120 minutes for initial diagnosisP055C relates to engine oil pressure sensor/switch b low. Check the fault conditions and vehicle-specific procedure before replacing parts.P055DEngine Oil Pressure Sensor/Switch B HighCheck soonEngine Problems30–120 minutes for initial diagnosisP055D relates to engine oil pressure sensor/switch b high. Check the fault conditions and vehicle-specific procedure before replacing parts.P055FEngine Oil Pressure Out of RangeCheck soonEngine Problems30–120 minutes for initial diagnosisP055F relates to engine oil pressure out of range. Check the fault conditions and vehicle-specific procedure before replacing parts.P0597Thermostat Heater Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP0597 relates to thermostat heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P0598Thermostat Heater Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP0598 relates to thermostat heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0599Thermostat Heater Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP0599 relates to thermostat heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P05C2Engine Coolant Pressure Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP05C2 relates to engine coolant pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P05C3Engine Coolant Pressure Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP05C3 relates to engine coolant pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.