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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.

Check soon 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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Diagnostic codes

Showing 4201–4224 of 6682

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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.P248EEGR Cooler Bypass Control Circuit/Open Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP248E relates to egr cooler bypass control circuit/open bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P248FEGR Cooler Bypass Control Circuit Range/Performance Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP248F relates to egr cooler bypass control circuit range/performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2490EGR Cooler Bypass Control Circuit Low Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP2490 relates to egr cooler bypass control circuit low bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2491EGR Cooler Bypass Control Circuit High Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP2491 relates to egr cooler bypass control circuit high bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2492EGR Cooler Bypass Position Sensor Circuit Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP2492 relates to egr cooler bypass position sensor circuit bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2493EGR Cooler Bypass Position Sensor Range/Performance Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP2493 relates to egr cooler bypass position sensor range/performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2494EGR Cooler Bypass Position Sensor Circuit Low Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP2494 relates to egr cooler bypass position sensor circuit low bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2495EGR Cooler Bypass Position Sensor Circuit High Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP2495 relates to egr cooler bypass position sensor circuit high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2496EGR Cooler Bypass Position Sensor Circuit Intermittent/Erratic Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP2496 relates to egr cooler bypass position sensor circuit intermittent/erratic bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2497EGR Cooler Bypass Position Sensor Circuit Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP2497 relates to egr cooler bypass position sensor circuit bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2498EGR Cooler Bypass Position Sensor Range/Performance Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP2498 relates to egr cooler bypass position sensor range/performance bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2499EGR Cooler Bypass Position Sensor Circuit Low Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP2499 relates to egr cooler bypass position sensor circuit low bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P249AEGR Cooler Bypass Position Sensor Circuit High Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP249A relates to egr cooler bypass position sensor circuit high bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P249BEGR Cooler Bypass Position Sensor Circuit Intermittent/Erratic Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP249B relates to egr cooler bypass position sensor circuit intermittent/erratic bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P249CExcessive Time To Enter Closed Loop Reductant Injection ControlCheck soonFuel System30–120 minutes for initial diagnosisP249C relates to excessive time to enter closed loop reductant injection control. Check the fault conditions and vehicle-specific procedure before replacing parts.P249DClosed Loop Reductant Injection Control At Limit - Flow Too LowCheck soonFuel System30–120 minutes for initial diagnosisP249D relates to closed loop reductant injection control at limit - flow too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P249EClosed Loop Reductant Injection Control At Limit - Flow Too HighCheck soonFuel System30–120 minutes for initial diagnosisP249E relates to closed loop reductant injection control at limit - flow too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P249FExcessive Time To Enter Closed Loop Particulate Filter Regeneration ControlCheck soonEmissions System30–120 minutes for initial diagnosisP249F relates to excessive time to enter closed loop particulate filter regeneration control. Check the fault conditions and vehicle-specific procedure before replacing parts.P24A0Closed Loop Particulate Filter Regeneration Control At Limit - Temperature Too LowCheck soonEmissions System30–120 minutes for initial diagnosisP24A0 relates to closed loop particulate filter regeneration control at limit - temperature too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P24A1Closed Loop Particulate Filter Regeneration Control At Limit - Temperature Too HighCheck soonEmissions System30–120 minutes for initial diagnosisP24A1 relates to closed loop particulate filter regeneration control at limit - temperature too high. Check the fault conditions and vehicle-specific procedure before replacing parts.P24A2Particulate Filter Regeneration Incomplete Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP24A2 relates to particulate filter regeneration incomplete bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P24A3Particulate Filter Restriction - Soot Accumulation Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP24A3 relates to particulate filter restriction - soot accumulation bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P24A4Particulate Filter Restriction - Soot Accumulation Too High Bank 1Check soonEmissions System30–120 minutes for initial diagnosisP24A4 relates to particulate filter restriction - soot accumulation too high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.