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9,253 diagnostic guides
Find codes by symptomChoose what you notice to search matching code guides.
Rough idle or shakingVibration while stoppedHard to startLong cranking or no-startEngine stallsCuts out at idle or on the roadHesitates or loses powerSlow response when acceleratingBattery light is onCharging system warningHarsh 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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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.
Diagnostic codes
Showing 4345–4368 of 6682
P2536Ignition Switch Accessory Position CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2537Ignition Switch Accessory Position Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2538Ignition Switch Accessory Position Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2539Low Pressure Fuel System Sensor CircuitCheck soonFuel System30–120 minutes for initial diagnosisP253APTO Sense Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253BPTO Sense Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253CPTO Sense Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253DPTO Sense Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253EPTO Sense Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP253FEngine Oil DeterioratedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2540Low Pressure Fuel System Sensor Circuit Range/PerformanceCheck soonFuel System30–120 minutes for initial diagnosisP2541Low Pressure Fuel System Sensor Circuit LowCheck soonFuel System30–120 minutes for initial diagnosisP2542Low Pressure Fuel System Sensor Circuit HighCheck soonFuel System30–120 minutes for initial diagnosisP2543Low Pressure Fuel System Sensor Circuit IntermittentCheck soonFuel System30–120 minutes for initial diagnosisP2544Torque Management Request Input Signal ACheck soonSensors & Electronics30–120 minutes for initial diagnosisP2545Torque Management Request Input Signal A Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2546Torque Management Request Input Signal A LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2547Torque Management Request Input Signal A HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2548Torque Management Request Input Signal BCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2549Torque Management Request Input Signal B Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254APTO Speed Selector Sensor/Switch 1 Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254BPTO Speed Selector Sensor/Switch 1 Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254CPTO Speed Selector Sensor/Switch 1 Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP254DPTO Speed Selector Sensor/Switch 1 Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosis