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9,253 diagnostic guides

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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 145–168 of 378

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P2145EGR Vent Control Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP2145 relates to egr vent control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P214ASCR NOx Catalyst Inlet Temperature Too HighCheck soonEmissions System30–120 minutes for initial diagnosisP214A relates to scr nox catalyst inlet temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P214BSCR NOx Catalyst Inlet Temperature Too High During Particulate Filter RegenerationCheck soonEmissions System30–120 minutes for initial diagnosisP214B relates to scr nox catalyst inlet temperature too high during particulate filter regeneration. Check the fault conditions and vehicle-specific procedure before replacing parts.P214CSCR NOx Catalyst Outlet Temperature Too HighCheck soonEmissions System30–120 minutes for initial diagnosisP214C relates to scr nox catalyst outlet temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P214DSCR NOx Catalyst Outlet Temperature Too High During Particulate Filter RegenerationCheck soonEmissions System30–120 minutes for initial diagnosisP214D relates to scr nox catalyst outlet temperature too high during particulate filter regeneration. Check the fault conditions and vehicle-specific procedure before replacing parts.P226DParticulate Filter Deteriorated/Missing Substrate Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP226D relates to particulate filter deteriorated/missing substrate bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P226EParticulate Filter Deteriorated/Missing Substrate Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP226E relates to particulate filter deteriorated/missing substrate bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P22FFSCR NOx Catalyst Inlet Temperature Too LowCheck soonEmissions System30–120 minutes for initial diagnosisP22FF relates to scr nox catalyst inlet temperature too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2380EGR Sensor D CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP2380 relates to egr sensor d circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2381EGR Sensor D Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP2381 relates to egr sensor d circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2382EGR Sensor D Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP2382 relates to egr sensor d circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2383EGR Sensor D Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2383 relates to egr sensor d circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2384EGR Sensor D Circuit IntermittentCheck soonEmissions System30–120 minutes for initial diagnosisP2384 relates to egr sensor d circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P2385EGR Sensor E CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP2385 relates to egr sensor e circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2386EGR Sensor E Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP2386 relates to egr sensor e circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2387EGR Sensor E Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP2387 relates to egr sensor e circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2388EGR Sensor E Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP2388 relates to egr sensor e circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2389EGR Sensor E Circuit IntermittentCheck soonEmissions System30–120 minutes for initial diagnosisP2389 relates to egr sensor e circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E1EGR C Control Circuit/OpenCheck soonEmissions System30–120 minutes for initial diagnosisP23E1 relates to egr c control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E2EGR C Control Circuit PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP23E2 relates to egr c control circuit performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E3EGR C Control Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP23E3 relates to egr c control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E4EGR C Control Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP23E4 relates to egr c control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E5EGR C Control Stuck OpenCheck soonEmissions System30–120 minutes for initial diagnosisP23E5 relates to egr c control stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23E6EGR C Control Stuck ClosedCheck soonEmissions System30–120 minutes for initial diagnosisP23E6 relates to egr c control stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.