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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 5113–5136 of 7353

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P2634Fuel Pump B Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2634 relates to fuel pump b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2635Fuel Pump A Low Flow/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2635 relates to fuel pump a low flow/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2636Fuel Pump B Low Flow/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2636 relates to fuel pump b low flow/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2637Torque Management Feedback Signal ACheck soonSensors & Electronics30–120 minutes for initial diagnosisP2637 relates to torque management feedback signal a. Check the fault conditions and vehicle-specific procedure before replacing parts.P2638Torque Management Feedback Signal A Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2638 relates to torque management feedback signal a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2639Torque Management Feedback Signal A LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2639 relates to torque management feedback signal a low. Check the fault conditions and vehicle-specific procedure before replacing parts.P263AMIL Control Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP263A relates to mil control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P263BMIL Control Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP263B relates to mil control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P263CGlow Plug Control Driver PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP263C relates to glow plug control driver performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P263DReductant Heater Driver PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP263D relates to reductant heater driver performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P263EGlow Plug Control Module 1 Over TemperatureUrgentSensors & Electronics30–120 minutes for initial diagnosisP263E relates to glow plug control module 1 over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P263FGlow Plug Control Module 2 Over TemperatureUrgentSensors & Electronics30–120 minutes for initial diagnosisP263F relates to glow plug control module 2 over temperature. Check the fault conditions and vehicle-specific procedure before replacing parts.P2640Torque Management Feedback Signal A HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2640 relates to torque management feedback signal a high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2641Torque Management Feedback Signal BCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2641 relates to torque management feedback signal b. Check the fault conditions and vehicle-specific procedure before replacing parts.P2642Torque Management Feedback Signal B Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2642 relates to torque management feedback signal b range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2643Torque Management Feedback Signal B LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2643 relates to torque management feedback signal b low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2644Torque Management Feedback Signal B HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2644 relates to torque management feedback signal b high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2645A Rocker Arm Actuator Control Circuit/Open Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2645 relates to a rocker arm actuator control circuit/open bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2646A Rocker Arm Actuator System Performance/Stuck Off Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2646 relates to a rocker arm actuator system performance/stuck off bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2647A Rocker Arm Actuator System Stuck On Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2647 relates to a rocker arm actuator system stuck on bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2648A Rocker Arm Actuator Control Circuit Low Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2648 relates to a rocker arm actuator control circuit low bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2649A Rocker Arm Actuator Control Circuit High Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2649 relates to a rocker arm actuator control circuit high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P264AA Rocker Arm Actuator Position Sensor Circuit Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP264A relates to a rocker arm actuator position sensor circuit bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P264BA Rocker Arm Actuator Position Sensor Circuit Range/Performance Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP264B relates to a rocker arm actuator position sensor circuit range/performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.