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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.

Check soon P · Powertrain Clear all

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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 1009–1032 of 6682

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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.P052EPCV Regulator Valve PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP052E relates to pcv regulator valve performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P052FGlow Plug Control Module 1 System VoltageCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP052F relates to glow plug control module 1 system voltage. Check the fault conditions and vehicle-specific procedure before replacing parts.P053APCV Heater A Control Circuit /OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP053A relates to pcv heater a control circuit /open. Check the fault conditions and vehicle-specific procedure before replacing parts.P053BPCV Heater A Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP053B relates to pcv heater a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P053CPCV Heater A Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP053C relates to pcv heater a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P053DPCV Heater A PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP053D relates to pcv heater a performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P053ECrankcase Pressure Too HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP053E relates to crankcase pressure too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P053FCold Start Fuel Pressure Performance Bank 1Check soonFuel System30–120 minutes for initial diagnosisP053F relates to cold start fuel pressure performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0540Intake Air Heater A CircuitCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0540 indicates a fault related to intake air heater a circuit. Learn the likely causes and a practical diagnostic order before replacing parts.P0541Intake Air Heater A Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0541 indicates a fault related to intake air heater a circuit low. Learn the likely causes and a practical diagnostic order before replacing parts.P0542Intake Air Heater A Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0542 indicates a fault related to intake air heater a circuit high. Learn the likely causes and a practical diagnostic order before replacing parts.P0543Intake Air Heater A Circuit OpenCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0543 indicates a fault related to intake air heater a circuit open. Learn the likely causes and a practical diagnostic order before replacing parts.P0544Exhaust Gas Temperature Sensor Circuit Bank 1 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0544 indicates a fault related to exhaust gas temperature sensor circuit bank 1 sensor 1. Learn the likely causes and a practical diagnostic order before replacing parts.P0545Exhaust Gas Temperature Sensor Circuit Low Bank 1 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0545 relates to exhaust gas temperature sensor circuit low bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0546Exhaust Gas Temperature Sensor Circuit High Bank 1 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0546 relates to exhaust gas temperature sensor circuit high bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0547Exhaust Gas Temperature Sensor Circuit Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0547 relates to exhaust gas temperature sensor circuit bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.