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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 5017–5040 of 8256

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P269AExhaust Aftertreatment Fuel Injector A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP269A relates to exhaust aftertreatment fuel injector a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P269BExhaust Aftertreatment Glow Plug Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP269B relates to exhaust aftertreatment glow plug control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P269CExhaust Aftertreatment Glow Plug Control PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP269C relates to exhaust aftertreatment glow plug control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P269DExhaust Aftertreatment Glow Plug Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP269D relates to exhaust aftertreatment glow plug control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P269EExhaust Aftertreatment Glow Plug Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP269E relates to exhaust aftertreatment glow plug control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P269FExhaust Aftertreatment Glow Plug Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP269F relates to exhaust aftertreatment glow plug circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A0Exhaust Aftertreatment Glow Plug PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP26A0 relates to exhaust aftertreatment glow plug performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A1Exhaust Aftertreatment Glow Plug Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP26A1 relates to exhaust aftertreatment glow plug circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P26A2Exhaust Aftertreatment Glow Plug Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP26A2 relates to exhaust aftertreatment glow plug 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.