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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

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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 1225–1248 of 1939

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P2430AIR System Air Flow/Pressure Sensor Circuit Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2430 relates to air system air flow/pressure sensor circuit bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2431AIR System Air Flow/Pressure Sensor Circuit Range/Performance Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2431 relates to air system air flow/pressure sensor circuit range/performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2432AIR System Air Flow/Pressure Sensor Circuit Low Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2432 relates to air system air flow/pressure sensor circuit low bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2433AIR System Air Flow/Pressure Sensor Circuit High Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2433 relates to air system air flow/pressure sensor circuit high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2434AIR System Air Flow/Pressure Sensor Circuit Intermittent/Erratic Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2434 relates to air system air flow/pressure sensor circuit intermittent/erratic bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2435AIR System Air Flow/Pressure Sensor Circuit Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2435 relates to air system air flow/pressure sensor circuit bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2436AIR System Air Flow/Pressure Sensor Circuit Range/Performance Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2436 relates to air system air flow/pressure sensor circuit range/performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2437AIR System Air Flow/Pressure Sensor Circuit Low Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2437 relates to air system air flow/pressure sensor circuit low bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2438AIR System Air Flow/Pressure Sensor Circuit High Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2438 relates to air system air flow/pressure sensor circuit high bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2439AIR System Air Flow/Pressure Sensor Circuit Intermittent/Erratic Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2439 relates to air system air flow/pressure sensor circuit intermittent/erratic bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2440AIR System Switching Valve Stuck Open Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2440 relates to air system switching valve stuck open bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2441AIR System Switching Valve Stuck Closed Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2441 relates to air system switching valve stuck closed bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2442AIR System Switching Valve Stuck Open Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2442 relates to air system switching valve stuck open bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2443AIR System Switching Valve Stuck Closed Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2443 relates to air system switching valve stuck closed bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2444AIR System Pump Stuck On Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2444 relates to air system pump stuck on bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2445AIR System Pump Stuck Off Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2445 relates to air system pump stuck off bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2446AIR System Pump Stuck On Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2446 relates to air system pump stuck on bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2447AIR System Pump Stuck Off Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2447 relates to air system pump stuck off bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2448AIR System High Air Flow Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2448 relates to air system high air flow bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2449AIR System High Air Flow Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2449 relates to air system high air flow bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P248AReductant Heater A Sense Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP248A relates to reductant heater a sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P248BReductant Heater A Sense Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP248B relates to reductant heater a sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P248CReductant Heater B Sense Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP248C relates to reductant heater b sense circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P248DReductant Heater B Sense Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP248D relates to reductant heater b sense circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.