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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 841–864 of 6682

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P042BCatalyst Temperature Sensor Circuit Range/Performance Bank 1 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP042B relates to catalyst temperature sensor circuit range/performance bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P042CCatalyst Temperature Sensor Circuit Low Bank 1 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP042C relates to catalyst temperature sensor circuit low bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P042DCatalyst Temperature Sensor Circuit High Bank 1 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP042D relates to catalyst temperature sensor circuit high bank 1 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P042EEGR A Control Stuck OpenCheck soonEmissions System30–120 minutes for initial diagnosisP042E relates to egr a control stuck open. Check the fault conditions and vehicle-specific procedure before replacing parts.P042FEGR A Control Stuck ClosedCheck soonEmissions System30–120 minutes for initial diagnosisP042F relates to egr a control stuck closed. Check the fault conditions and vehicle-specific procedure before replacing parts.P0434Heated Catalyst Temperature Below Threshold Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP0434 indicates a fault related to heated catalyst temperature below threshold bank 2. Learn the likely causes and a practical diagnostic order before replacing parts.P0435Catalyst Temperature Sensor Circuit Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0435 relates to catalyst temperature sensor circuit bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0436Catalyst Temperature Sensor Circuit Range/Performance Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0436 relates to catalyst temperature sensor circuit range/performance bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0437Catalyst Temperature Sensor Circuit Low Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0437 relates to catalyst temperature sensor circuit low bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0438Catalyst Temperature Sensor Circuit High Bank 2 Sensor 1Check soonEmissions System30–120 minutes for initial diagnosisP0438 relates to catalyst temperature sensor circuit high bank 2 sensor 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P0439Catalyst Heater Control Circuit/Open Bank 2Check soonEmissions System30–120 minutes for initial diagnosisP0439 relates to catalyst heater control circuit/open bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P043ACatalyst Temperature Sensor Circuit Bank 2 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP043A relates to catalyst temperature sensor circuit bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P043BCatalyst Temperature Sensor Circuit Range/Performance Bank 2 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP043B relates to catalyst temperature sensor circuit range/performance bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P043CCatalyst Temperature Sensor Circuit Low Bank 2 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP043C relates to catalyst temperature sensor circuit low bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P043DCatalyst Temperature Sensor Circuit High Bank 2 Sensor 2Check soonEmissions System30–120 minutes for initial diagnosisP043D relates to catalyst temperature sensor circuit high bank 2 sensor 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P044AEGR Sensor C CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP044A relates to egr sensor c circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P044BEGR Sensor C Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP044B relates to egr sensor c circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P044CEGR Sensor C Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP044C relates to egr sensor c circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P044DEGR Sensor C Circuit HighCheck soonEmissions System30–120 minutes for initial diagnosisP044D relates to egr sensor c circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P044EEGR Sensor C Circuit Intermittent/ErraticCheck soonEmissions System30–120 minutes for initial diagnosisP044E relates to egr sensor c circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P044FAIR System Switching Valve A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP044F relates to air system switching valve a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P045AEGR B Control CircuitCheck soonEmissions System30–120 minutes for initial diagnosisP045A relates to egr b control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P045BEGR B Control Circuit Range/PerformanceCheck soonEmissions System30–120 minutes for initial diagnosisP045B relates to egr b control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P045CEGR B Control Circuit LowCheck soonEmissions System30–120 minutes for initial diagnosisP045C relates to egr b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.