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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 5233–5256 of 7353

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P26ACEngine Coolant Bypass Valve B Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26AC relates to engine coolant bypass valve b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.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.P26B3Fuel Shutoff Valve A Control Circuit Performance/Stuck OffCheck soonFuel System30–120 minutes for initial diagnosisP26B3 relates to fuel shutoff valve a control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B4Fuel Shutoff Valve A Control Circuit Stuck OnCheck soonFuel System30–120 minutes for initial diagnosisP26B4 relates to fuel shutoff valve a control circuit stuck on. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B5Fuel Shutoff Valve B Control Circuit Performance/Stuck OffCheck soonFuel System30–120 minutes for initial diagnosisP26B5 relates to fuel shutoff valve b control circuit performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P26B6Fuel Shutoff Valve B Control Circuit Stuck OnCheck soonFuel System30–120 minutes for initial diagnosisP26B6 relates to fuel shutoff valve b control circuit stuck on. 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.P26C3Internal Control Module Transmission Range Sensor PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP26C3 relates to internal control module transmission range sensor performance. Check the fault conditions and vehicle-specific procedure before replacing parts.