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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.

Sensors & Electronics 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 1297–1320 of 2110

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P23A9Communication Fault – Forced Engine ShutdownCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23A9 relates to communication fault – forced engine shutdown. Check the fault conditions and vehicle-specific procedure before replacing parts.P23AATurbocharger/Supercharger Bypass Valve A StuckCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23AA relates to turbocharger/supercharger bypass valve a stuck. Check the fault conditions and vehicle-specific procedure before replacing parts.P23ABNOx Sensor Processor Performance Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23AB relates to nox sensor processor performance bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23ACNOx Sensor Circuit Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23AC relates to nox sensor circuit bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23ADNOx Sensor Circuit Range/Performance Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23AD relates to nox sensor circuit range/performance bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23AENOx Sensor Circuit Low Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23AE relates to nox sensor circuit low bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23AFNOx Sensor Circuit High Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23AF relates to nox sensor circuit high bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B0NOx Sensor Circuit Intermittent Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B0 relates to nox sensor circuit intermittent bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.P23B1NOx Sensor Heater Control Circuit/Open Bank 1 Sensor 3Check soonSensors & Electronics30–120 minutes for initial diagnosisP23B1 relates to nox sensor heater control circuit/open bank 1 sensor 3. Check the fault conditions and vehicle-specific procedure before replacing parts.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.