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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 529–552 of 1049

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P26ADEngine Coolant Bypass Valve B Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP26AD relates to engine coolant bypass valve b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P26AEEngine Coolant Bypass Valve B Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP26AE relates to engine coolant bypass valve b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P26AFEngine Coolant Bypass Valve B Stuck/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26AF relates to engine coolant bypass valve b stuck/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B0Engine Coolant Bypass Valve B Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26B0 relates to engine coolant bypass valve b range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B1Engine Coolant Bypass Valve A Stuck ClosedCheck soonEngine Problems30–120 minutes for initial diagnosisP26B1 relates to engine coolant bypass valve a stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B2Engine Coolant Bypass Valve B Stuck ClosedCheck soonEngine Problems30–120 minutes for initial diagnosisP26B2 relates to engine coolant bypass valve b stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B7Engine Coolant Bypass Valve C Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26B7 relates to engine coolant bypass valve c control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B8Engine Coolant Bypass Valve C Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP26B8 relates to engine coolant bypass valve c control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B9Engine Coolant Bypass Valve C Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP26B9 relates to engine coolant bypass valve c control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P26BAEngine Coolant Bypass Valve C Stuck/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26BA relates to engine coolant bypass valve c stuck/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P26BBEngine Coolant Bypass Valve C Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26BB relates to engine coolant bypass valve c range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26BCEngine Coolant Bypass Valve C Stuck ClosedCheck soonEngine Problems30–120 minutes for initial diagnosisP26BC relates to engine coolant bypass valve c stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P26BDEngine Coolant Bypass Valve D Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26BD relates to engine coolant bypass valve d control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P26BEEngine Coolant Bypass Valve D Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP26BE relates to engine coolant bypass valve d control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P26BFEngine Coolant Bypass Valve D Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP26BF relates to engine coolant bypass valve d control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P26C0Engine Coolant Bypass Valve D Stuck/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26C0 relates to engine coolant bypass valve d stuck/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P26C1Engine Coolant Bypass Valve D Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26C1 relates to engine coolant bypass valve d range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26C2Engine Coolant Bypass Valve D Stuck ClosedCheck soonEngine Problems30–120 minutes for initial diagnosisP26C2 relates to engine coolant bypass valve d stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P26CAEngine Coolant Pump Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26CA relates to engine coolant pump control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P26CBEngine Coolant Pump Performance/Stuck OffCheck soonEngine Problems30–120 minutes for initial diagnosisP26CB relates to engine coolant pump performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P26CCEngine Coolant Pump Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP26CC relates to engine coolant pump control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P26CDEngine Coolant Pump Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP26CD relates to engine coolant pump control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P26CEEngine Coolant Pump Overspeed/Air In SystemUrgentEngine Problems30–120 minutes for initial diagnosisP26CE relates to engine coolant pump overspeed/air in system. Check the fault conditions and vehicle-specific procedure before replacing parts.P26D2Engine Coolant Pump Control Module Over TemperatureUrgentEngine Problems30–120 minutes for initial diagnosisP26D2 relates to engine coolant pump control module over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.