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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 481–504 of 987

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P2679Coolant Degassing Valve Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2679 relates to coolant degassing valve control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2680Coolant Degassing Valve Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2680 relates to coolant degassing valve control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2681Engine Coolant Bypass Valve A Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP2681 relates to engine coolant bypass valve a control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2682Engine Coolant Bypass Valve A Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2682 relates to engine coolant bypass valve a control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2683Engine Coolant Bypass Valve A Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2683 relates to engine coolant bypass valve a control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A3Engine Coolant Bypass Valve A Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26A3 relates to engine coolant bypass valve a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A4Engine Coolant Bypass Valve A Position Sensor CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP26A4 relates to engine coolant bypass valve a position sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A5Engine Coolant Bypass Valve A Position Sensor Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26A5 relates to engine coolant bypass valve a position sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A6Engine Coolant Bypass Valve A Position Sensor Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP26A6 relates to engine coolant bypass valve a position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A7Engine Coolant Bypass Valve A Position Sensor Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP26A7 relates to engine coolant bypass valve a position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A8Engine Coolant Bypass Valve A Position Sensor Circuit Intermittent/ErraticCheck soonEngine Problems30–120 minutes for initial diagnosisP26A8 relates to engine coolant bypass valve a position sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A9Engine Coolant Bypass Valve A Position Sensor Stop/Minimum Stop PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26A9 relates to engine coolant bypass valve a position sensor stop/minimum stop performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26AAEngine Coolant Bypass Valve A Position Sensor Maximum Stop PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP26AA relates to engine coolant bypass valve a position sensor maximum stop performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26ABEngine Coolant Bypass Valve A Stuck/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP26AB relates to engine coolant bypass valve a stuck/open. Check the fault conditions and vehicle-specific procedure before replacing parts.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.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.