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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 4873–4896 of 7353

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P2544Torque Management Request Input Signal ACheck soonSensors & Electronics30–120 minutes for initial diagnosisP2544 relates to torque management request input signal a. Check the fault conditions and vehicle-specific procedure before replacing parts.P2545Torque Management Request Input Signal A Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2545 relates to torque management request input signal a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2546Torque Management Request Input Signal A LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2546 relates to torque management request input signal a low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2547Torque Management Request Input Signal A HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2547 relates to torque management request input signal a high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2548Torque Management Request Input Signal BCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2548 relates to torque management request input signal b. Check the fault conditions and vehicle-specific procedure before replacing parts.P2549Torque Management Request Input Signal B Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2549 relates to torque management request input signal b range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P254APTO Speed Selector Sensor/Switch 1 Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254A relates to pto speed selector sensor/switch 1 circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P254BPTO Speed Selector Sensor/Switch 1 Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254B relates to pto speed selector sensor/switch 1 range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P254CPTO Speed Selector Sensor/Switch 1 Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254C relates to pto speed selector sensor/switch 1 circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P254DPTO Speed Selector Sensor/Switch 1 Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254D relates to pto speed selector sensor/switch 1 circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P254EPTO Speed Selector Sensor/Switch 1 Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254E relates to pto speed selector sensor/switch 1 circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P254FEngine Hood Switch CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254F relates to engine hood switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2550Torque Management Request Input Signal B LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2550 relates to torque management request input signal b low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2551Torque Management Request Input Signal B HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2551 relates to torque management request input signal b high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2552Throttle/Fuel Inhibit A CircuitCheck soonFuel System30–120 minutes for initial diagnosisP2552 relates to throttle/fuel inhibit a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2553Throttle/Fuel Inhibit A Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2553 relates to throttle/fuel inhibit a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2554Throttle/Fuel Inhibit A Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2554 relates to throttle/fuel inhibit a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2555Throttle/Fuel Inhibit A Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2555 relates to throttle/fuel inhibit a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2556Engine Coolant Level Sensor/Switch CircuitCheck soonEngine Problems30–120 minutes for initial diagnosisP2556 relates to engine coolant level sensor/switch circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2557Engine Coolant Level Sensor/Switch Circuit Range/PerformanceCheck soonEngine Problems30–120 minutes for initial diagnosisP2557 relates to engine coolant level sensor/switch circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2558Engine Coolant Level Sensor/Switch Circuit LowCheck soonEngine Problems30–120 minutes for initial diagnosisP2558 relates to engine coolant level sensor/switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2559Engine Coolant Level Sensor/Switch Circuit HighCheck soonEngine Problems30–120 minutes for initial diagnosisP2559 relates to engine coolant level sensor/switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P255APTO Speed Selector Sensor/Switch 2 Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP255A relates to pto speed selector sensor/switch 2 circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P255BPTO Speed Selector Sensor/Switch 2 Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP255B relates to pto speed selector sensor/switch 2 range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.