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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 1321–1344 of 2110

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P23C2NOx Sensor Delayed Response - High to Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23C2 relates to nox sensor delayed response - high to low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2414O2 Sensor Exhaust Sample Error Bank 1 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2414 relates to o2 sensor exhaust sample error bank 1 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2415O2 Sensor Exhaust Sample Error Bank 2 Sensor 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2415 relates to o2 sensor exhaust sample error bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2416O2 Sensor Signals Swapped Bank 1 Sensor 2/Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2416 relates to o2 sensor signals swapped bank 1 sensor 2/bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P2417O2 Sensor Signals Swapped Bank 2 Sensor 2/Bank 2 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP2417 relates to o2 sensor signals swapped bank 2 sensor 2/bank 2 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P241AO2 Sensor Signals Swapped Bank 1 Sensor 1/Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP241A relates to o2 sensor signals swapped bank 1 sensor 1/bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P241BO2 Sensor Signals Swapped Bank 2 Sensor 1/Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP241B relates to o2 sensor signals swapped bank 2 sensor 1/bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P241CThrottle Actuator Control System - Ice Blockage Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP241C relates to throttle actuator control system - ice blockage bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P241DSCR Inducement - Forced Engine ShutdownCheck soonSensors & Electronics30–120 minutes for initial diagnosisP241D relates to scr inducement - forced engine shutdown. Check the fault conditions and vehicle-specific procedure before replacing parts.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.