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9,253 diagnostic guides

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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

FiltersSeverity · family

Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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 457–480 of 1016

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P21B7Cold Start Cylinder 2 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21B7 relates to cold start cylinder 2 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B8Cold Start Cylinder 3 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21B8 relates to cold start cylinder 3 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21B9Cold Start Cylinder 4 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21B9 relates to cold start cylinder 4 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21BACold Start Cylinder 5 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21BA relates to cold start cylinder 5 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21BBCold Start Cylinder 6 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21BB relates to cold start cylinder 6 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21BCCold Start Cylinder 7 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21BC relates to cold start cylinder 7 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21BDCold Start Cylinder 8 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21BD relates to cold start cylinder 8 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21BECold Start Cylinder 9 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21BE relates to cold start cylinder 9 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21BFCold Start Cylinder 10 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21BF relates to cold start cylinder 10 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21C0Cold Start Cylinder 11 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21C0 relates to cold start cylinder 11 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21C1Cold Start Cylinder 12 Injection TimingCheck soonFuel System30–120 minutes for initial diagnosisP21C1 relates to cold start cylinder 12 injection timing. Check the fault conditions and vehicle-specific procedure before replacing parts.P21CFCylinder 1 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21CF relates to cylinder 1 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D0Cylinder 2 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D0 relates to cylinder 2 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D1Cylinder 3 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D1 relates to cylinder 3 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D2Cylinder 4 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D2 relates to cylinder 4 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D3Cylinder 5 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D3 relates to cylinder 5 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D4Cylinder 6 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D4 relates to cylinder 6 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D5Cylinder 7 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D5 relates to cylinder 7 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D6Cylinder 8 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D6 relates to cylinder 8 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D7Cylinder 9 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D7 relates to cylinder 9 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D8Cylinder 10 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D8 relates to cylinder 10 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21D9Cylinder 11 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21D9 relates to cylinder 11 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21DACylinder 12 Injector B Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP21DA relates to cylinder 12 injector b circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P21DBCylinder 1 Injector B Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP21DB relates to cylinder 1 injector b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.