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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 1273–1296 of 2110

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P2391Diesel Intake Air Flow B Control PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2391 relates to diesel intake air flow b control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2392Diesel Intake Air Flow B Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2392 relates to diesel intake air flow b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2393Diesel Intake Air Flow B Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2393 relates to diesel intake air flow b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2394Diesel Intake Air Flow B Control Stuck OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2394 relates to diesel intake air flow b control stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2395Diesel Intake Air Flow B Control Stuck ClosedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2395 relates to diesel intake air flow b control stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P2396Diesel Intake Air Flow B Position Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2396 relates to diesel intake air flow b position sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2397Diesel Intake Air Flow B Position Sensor Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2397 relates to diesel intake air flow b position sensor range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2398Diesel Intake Air Flow B Position Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2398 relates to diesel intake air flow b position sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2399Diesel Intake Air Flow B Position Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2399 relates to diesel intake air flow b position sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P239ADiesel Intake Air Flow B Position Sensor Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP239A relates to diesel intake air flow b position sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P239BDiesel Intake Air Flow B Control Motor Current Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP239B relates to diesel intake air flow b control motor current range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P239CDiesel Intake Air Flow B Control System - High Air Flow DetectedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP239C relates to diesel intake air flow b control system - high air flow detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P239DDiesel Intake Air Flow B Control System - Low Air Flow DetectedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP239D relates to diesel intake air flow b control system - low air flow detected. Check the fault conditions and vehicle-specific procedure before replacing parts.P239EO2 Sensor Out of Range During Deceleration Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP239E relates to o2 sensor out of range during deceleration bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P239FO2 Sensor Out of Range During Deceleration Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP239F relates to o2 sensor out of range during deceleration bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A0O2 Sensor Exhaust Sample Error Bank 1 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP23A0 relates to o2 sensor exhaust sample error bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A1O2 Sensor Exhaust Sample Error Bank 2 Sensor 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP23A1 relates to o2 sensor exhaust sample error bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A2Exhaust Heat Exchanger Exhaust Bypass Valve B Control Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23A2 relates to exhaust heat exchanger exhaust bypass valve b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A3Exhaust Heat Exchanger Exhaust Bypass Valve B Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23A3 relates to exhaust heat exchanger exhaust bypass valve b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A4Exhaust Heat Exchanger Exhaust Bypass Valve B Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23A4 relates to exhaust heat exchanger exhaust bypass valve b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A5Exhaust Heat Exchanger Exhaust Bypass Valve B Control PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23A5 relates to exhaust heat exchanger exhaust bypass valve b control performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A6Exhaust Heat Exchanger Exhaust Bypass Valve B Stuck OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23A6 relates to exhaust heat exchanger exhaust bypass valve b stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A7Exhaust Heat Exchanger Exhaust Bypass Valve B Stuck ClosedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23A7 relates to exhaust heat exchanger exhaust bypass valve b stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P23A8Exhaust Heat Exchanger Exhaust Bypass Valve B Position Sensor Stop PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP23A8 relates to exhaust heat exchanger exhaust bypass valve b position sensor stop performance. Check the fault conditions and vehicle-specific procedure before replacing parts.