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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 1201–1224 of 1939

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P23B2NOx Sensor Heater Control Circuit Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B2 relates to nox sensor heater control circuit low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B3NOx Sensor Heater Control Circuit High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B3 relates to nox sensor heater control circuit high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B4NOx Sensor Heater Sense Circuit Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B4 relates to nox sensor heater sense circuit bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B5NOx Sensor Heater Sense Circuit Range/Performance Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B5 relates to nox sensor heater sense circuit range/performance bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B7NOx Sensor Heater Control Circuit Range/Performance Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B7 relates to nox sensor heater control circuit range/performance bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B8NOx Sensor Heater Sense Circuit Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B8 relates to nox sensor heater sense circuit low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B9NOx Sensor Heater Sense Circuit High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B9 relates to nox sensor heater sense circuit high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BANOx Sensor Heater Sense Circuit Intermittent Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BA relates to nox sensor heater sense circuit intermittent bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BBNOx Sensor Heater Resistance Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BB relates to nox sensor heater resistance bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BCNOx Sensor Calibration Memory Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BC relates to nox sensor calibration memory bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BDNOx Sensor Performance - Signal Biased/Stuck High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BD relates to nox sensor performance - signal biased/stuck high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BENOx Sensor Performance - Signal Biased/Stuck Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BE relates to nox sensor performance - signal biased/stuck low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23BFNOx Sensor Performance - Slow Response Low to High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23BF relates to nox sensor performance - slow response low to high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C0NOx Sensor Performance - Slow Response High to Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23C0 relates to nox sensor performance - slow response high to low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23C1NOx Sensor Performance - Sensing Element Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23C1 relates to nox sensor performance - sensing element bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.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.