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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 4489–4512 of 7353

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P23C4Engine Coolant Bypass Valve C Position Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP23C4 relates to engine coolant bypass valve c position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C5Engine Coolant Bypass Valve C Position Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP23C5 relates to engine coolant bypass valve c position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C6Engine Coolant Bypass Valve C Control Circuit Driver Current/Temperature Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP23C6 relates to engine coolant bypass valve c control circuit driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C7Fuel Heater Control Module Power Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23C7 relates to fuel heater control module power control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C8Fuel Heater Control Module Power Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23C8 relates to fuel heater control module power control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C9Fuel Heater Control Module Power Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23C9 relates to fuel heater control module power control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23CAFuel Rail Heater Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23CA relates to fuel rail heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23CBFuel Rail Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23CB relates to fuel rail heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23CCFuel Rail Heater Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23CC relates to fuel rail heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23CDFuel Heater Control Module Feedback Signal/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23CD relates to fuel heater control module feedback signal/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23CEFuel Heater Control Module Feedback Signal PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP23CE relates to fuel heater control module feedback signal performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23CFFuel Heater Control Module Feedback Signal Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23CF relates to fuel heater control module feedback signal circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D0Fuel Heater Control Module Feedback Signal Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23D0 relates to fuel heater control module feedback signal circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D1Cylinder 1 Fuel Heater Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23D1 relates to cylinder 1 fuel heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D2Cylinder 1 Fuel Heater Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23D2 relates to cylinder 1 fuel heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D3Cylinder 1 Fuel Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23D3 relates to cylinder 1 fuel heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D4Cylinder 1 Fuel Heater PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP23D4 relates to cylinder 1 fuel heater performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D5Cylinder 2 Fuel Heater Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23D5 relates to cylinder 2 fuel heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D6Cylinder 2 Fuel Heater Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23D6 relates to cylinder 2 fuel heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D7Cylinder 2 Fuel Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23D7 relates to cylinder 2 fuel heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D8Cylinder 2 Fuel Heater PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP23D8 relates to cylinder 2 fuel heater performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23D9Cylinder 3 Fuel Heater Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP23D9 relates to cylinder 3 fuel heater control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23DACylinder 3 Fuel Heater Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP23DA relates to cylinder 3 fuel heater control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23DBCylinder 3 Fuel Heater Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP23DB relates to cylinder 3 fuel heater control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.