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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 49–72 of 987

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P017CCylinder Head Temperature Sensor A Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP017C relates to cylinder head temperature sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P017DCylinder Head Temperature Sensor A Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP017D relates to cylinder head temperature sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P017ECylinder Head Temperature Sensor A Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP017E relates to cylinder head temperature sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P01E3Engine Coolant Temperature Sensor 3 CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP01E3 relates to engine coolant temperature sensor 3 circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P01E4Engine Coolant Temperature Sensor 3 Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP01E4 relates to engine coolant temperature sensor 3 circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P01E5Engine Coolant Temperature Sensor 3 Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP01E5 relates to engine coolant temperature sensor 3 circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P01E6Engine Coolant Temperature Sensor 3 Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP01E6 relates to engine coolant temperature sensor 3 circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P01E7Engine Coolant Temperature Sensor 3 Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP01E7 relates to engine coolant temperature sensor 3 circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P01E8Engine Coolant Heater A Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP01E8 relates to engine coolant heater a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P01E9Engine Coolant Heater A Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP01E9 relates to engine coolant heater a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P01EAEngine Coolant Heater A Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP01EA relates to engine coolant heater a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P01EBEngine Coolant Heater A Control Circuit PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP01EB relates to engine coolant heater a control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P01ECEngine Coolant Heater B Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP01EC relates to engine coolant heater b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P01EDEngine Coolant Heater B Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP01ED relates to engine coolant heater b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P01EEEngine Coolant Heater B Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP01EE relates to engine coolant heater b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P01EFEngine Coolant Heater B Control Circuit PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP01EF relates to engine coolant heater b control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F0Coolant Temperature Relapsed Below Diagnostic Monitoring TemperatureCheck soonEngine Problems30–120 minutes for initial diagnosisP01F0 relates to coolant temperature relapsed below diagnostic monitoring temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F8Engine Coolant Heater A Control Circuit Driver Current/Temperature Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP01F8 relates to engine coolant heater a control circuit driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P01F9Engine Coolant Heater B Control Circuit Driver Current/Temperature Too HighCheck soonEngine Problems30–120 minutes for initial diagnosisP01F9 relates to engine coolant heater b control circuit driver current/temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P023ACharge Air Cooler Coolant Pump A Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP023A relates to charge air cooler coolant pump a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P023BCharge Air Cooler Coolant Pump A Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP023B relates to charge air cooler coolant pump a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P023CCharge Air Cooler Coolant Pump A Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP023C relates to charge air cooler coolant pump a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0263Cylinder 1 Contribution/BalanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0263 relates to cylinder 1 contribution/balance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0266Cylinder 2 Contribution/BalanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0266 relates to cylinder 2 contribution/balance. Check the fault conditions and vehicle-specific procedure before replacing parts.