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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.

Check soon P · Powertrain Clear all

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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 457–480 of 6682

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P0278Cylinder 6 Contribution/BalanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0278 relates to cylinder 6 contribution/balance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0279Cylinder 7 Injector A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP0279 relates to cylinder 7 injector a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P027AFuel Pump Module B Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP027A relates to fuel pump module b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P027BFuel Pump Module B Control Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP027B relates to fuel pump module b control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P027CFuel Pump Module B Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP027C relates to fuel pump module b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P027DFuel Pump Module B Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP027D relates to fuel pump module b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P027ECold Start Fuel Injection Quantity A Lower Than ExpectedCheck soonFuel System30–120 minutes for initial diagnosisP027E relates to cold start fuel injection quantity a lower than expected. Check the fault conditions and vehicle-specific procedure before replacing parts.P027FCold Start Fuel Injection Quantity A Higher Than ExpectedCheck soonFuel System30–120 minutes for initial diagnosisP027F relates to cold start fuel injection quantity a higher than expected. Check the fault conditions and vehicle-specific procedure before replacing parts.P0280Cylinder 7 Injector A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP0280 relates to cylinder 7 injector a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0281Cylinder 7 Contribution/BalanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0281 relates to cylinder 7 contribution/balance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0282Cylinder 8 Injector A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP0282 relates to cylinder 8 injector a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0283Cylinder 8 Injector A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP0283 relates to cylinder 8 injector a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0284Cylinder 8 Contribution/BalanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0284 relates to cylinder 8 contribution/balance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0285Cylinder 9 Injector A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP0285 relates to cylinder 9 injector a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0286Cylinder 9 Injector A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP0286 relates to cylinder 9 injector a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0287Cylinder 9 Contribution/BalanceCheck soonEngine Problems30–120 minutes for initial diagnosisP0287 relates to cylinder 9 contribution/balance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0288Cylinder 10 Injector A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP0288 relates to cylinder 10 injector a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0289Cylinder 10 Injector A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP0289 relates to cylinder 10 injector a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P028ACharge Air Cooler Cooling Fan Control Circuit/OpenCheck soonEngine Problems30–120 minutes for initial diagnosisP028A relates to charge air cooler cooling fan control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P028BCharge Air Cooler Cooling Fan Performance/Stuck OffCheck soonEngine Problems30–120 minutes for initial diagnosisP028B relates to charge air cooler cooling fan performance/stuck off. Check the fault conditions and vehicle-specific procedure before replacing parts.P028CCharge Air Cooler Cooling Fan Stuck OnCheck soonEngine Problems30–120 minutes for initial diagnosisP028C relates to charge air cooler cooling fan stuck on. Check the fault conditions and vehicle-specific procedure before replacing parts.P028DCharge Air Cooler Cooling Fan Control Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP028D relates to charge air cooler cooling fan control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P028ECharge Air Cooler Cooling Fan Control Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP028E relates to charge air cooler cooling fan control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P028FCharge Air Cooler Cooling Fan Control Circuit Driver PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP028F relates to charge air cooler cooling fan control circuit driver performance. Check the fault conditions and vehicle-specific procedure before replacing parts.