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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.

Electrical & Charging System 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 49–72 of 1797

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P0616Starter Relay A Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0616 relates to starter relay a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0617Starter Relay A Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0617 relates to starter relay a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0623Generator Lamp Control CircuitCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0623 relates to generator lamp control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0625Generator Field/F Terminal Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0625 relates to generator field/f terminal circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0626Generator Field/F Terminal Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0626 relates to generator field/f terminal circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0635Power Steering Control CircuitCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0635 relates to power steering control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0636Power Steering Control Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0636 relates to power steering control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0637Power Steering Control Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0637 relates to power steering control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P063AGenerator Voltage Sense Circuit ACheck soonElectrical & Charging System30–120 minutes for initial diagnosisP063A relates to generator voltage sense circuit a. Check the fault conditions and vehicle-specific procedure before replacing parts.P063BGenerator Voltage Sense Circuit A Range/PerformanceCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP063B relates to generator voltage sense circuit a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P063CGenerator Voltage Sense Circuit A LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP063C relates to generator voltage sense circuit a low. Check the fault conditions and vehicle-specific procedure before replacing parts.P063DGenerator Voltage Sense Circuit A HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP063D relates to generator voltage sense circuit a high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0641Sensor Reference Voltage A Circuit/OpenCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0641 relates to sensor reference voltage a circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P0642Sensor Reference Voltage A Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0642 relates to sensor reference voltage a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0643Sensor Reference Voltage A Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0643 relates to sensor reference voltage a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0651Sensor Reference Voltage B Circuit/OpenCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0651 relates to sensor reference voltage b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P0652Sensor Reference Voltage B Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0652 relates to sensor reference voltage b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0653Sensor Reference Voltage B Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0653 relates to sensor reference voltage b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0657Actuator Supply Voltage A Circuit/OpenCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0657 relates to actuator supply voltage a circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P0658Actuator Supply Voltage A Circuit LowCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0658 relates to actuator supply voltage a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0659Actuator Supply Voltage A Circuit HighCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP0659 relates to actuator supply voltage a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P065AGenerator System PerformanceCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP065A relates to generator system performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P065BGenerator A Control Circuit Range/PerformanceCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP065B relates to generator a control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P065CGenerator A Mechanical PerformanceCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP065C relates to generator a mechanical performance. Check the fault conditions and vehicle-specific procedure before replacing parts.