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Find codes by symptomChoose what you notice to search matching code guides.

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 1585–1608 of 2110

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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.P264CA Rocker Arm Actuator Position Sensor Circuit Low Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP264C relates to a rocker arm actuator position sensor circuit low bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P264DA Rocker Arm Actuator Position Sensor Circuit High Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP264D relates to a rocker arm actuator position sensor circuit high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P264EA Rocker Arm Actuator Position Sensor Circuit Intermittent/Erratic Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP264E relates to a rocker arm actuator position sensor circuit intermittent/erratic bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P264FEngine Serial Number Not Programmed or IncompatibleCheck soonSensors & Electronics30–120 minutes for initial diagnosisP264F relates to engine serial number not programmed or incompatible. Check the fault conditions and vehicle-specific procedure before replacing parts.P2650B Rocker Arm Actuator Control Circuit/Open Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2650 relates to b rocker arm actuator control circuit/open bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2651B Rocker Arm Actuator System Performance/Stuck Off Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2651 relates to b rocker arm actuator system performance/stuck off bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2652B Rocker Arm Actuator System Stuck On Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2652 relates to b rocker arm actuator system stuck on bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2653B Rocker Arm Actuator Control Circuit Low Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2653 relates to b rocker arm actuator control circuit low bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2654B Rocker Arm Actuator Control Circuit High Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP2654 relates to b rocker arm actuator control circuit high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2655A Rocker Arm Actuator Control Circuit/Open Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2655 relates to a rocker arm actuator control circuit/open bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2656A Rocker Arm Actuator System Performance/Stuck Off Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2656 relates to a rocker arm actuator system performance/stuck off bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2657A Rocker Arm Actuator System Stuck On Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2657 relates to a rocker arm actuator system stuck on bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2658A Rocker Arm Actuator Control Circuit Low Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2658 relates to a rocker arm actuator control circuit low bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2659A Rocker Arm Actuator Control Circuit High Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2659 relates to a rocker arm actuator control circuit high bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P265AB Rocker Arm Actuator Position Sensor Circuit Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP265A relates to b rocker arm actuator position sensor circuit bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P265BB Rocker Arm Actuator Position Sensor Circuit Range/Performance Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP265B relates to b rocker arm actuator position sensor circuit range/performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P265CB Rocker Arm Actuator Position Sensor Circuit Low Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP265C relates to b rocker arm actuator position sensor circuit low bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P265DB Rocker Arm Actuator Position Sensor Circuit High Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP265D relates to b rocker arm actuator position sensor circuit high bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.