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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 4945–4968 of 8256

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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.P265EB Rocker Arm Actuator Position Sensor Circuit Intermittent/Erratic Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP265E relates to b rocker arm actuator position sensor circuit intermittent/erratic bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P2660B Rocker Arm Actuator Control Circuit/Open Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2660 relates to b rocker arm actuator control circuit/open bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2661B Rocker Arm Actuator System Performance/Stuck Off Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2661 relates to b rocker arm actuator system performance/stuck off bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2662B Rocker Arm Actuator System Stuck On Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2662 relates to b rocker arm actuator system stuck on bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2663B Rocker Arm Actuator Control Circuit Low Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2663 relates to b rocker arm actuator control circuit low bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2664B Rocker Arm Actuator Control Circuit High Bank 2Check soonSensors & Electronics30–120 minutes for initial diagnosisP2664 relates to b rocker arm actuator control circuit high bank 2. Check the fault conditions and vehicle-specific procedure before replacing parts.P2665Fuel Shutoff Valve B Control Circuit/OpenCheck soonFuel System30–120 minutes for initial diagnosisP2665 relates to fuel shutoff valve b control circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P2666Fuel Shutoff Valve B Control Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2666 relates to fuel shutoff valve b control circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2667Fuel Shutoff Valve B Control Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2667 relates to fuel shutoff valve b control circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2668Fuel Mode Indicator Lamp Control CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2668 relates to fuel mode indicator lamp control circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2669Actuator Supply Voltage B Circuit /OpenCheck soonElectrical & Charging System30–120 minutes for initial diagnosisP2669 relates to actuator supply voltage b circuit /open. Check the fault conditions and vehicle-specific procedure before replacing parts.