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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 1921–1944 of 7353

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P0838Four Wheel Drive (4WD) Switch Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0838 relates to four wheel drive (4wd) switch circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0839Four Wheel Drive (4WD) Switch Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0839 relates to four wheel drive (4wd) switch circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P083ATransmission Fluid Pressure Sensor/Switch G CircuitCheck soonTransmission Issues30–120 minutes for initial diagnosisP083A relates to transmission fluid pressure sensor/switch g circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P083BTransmission Fluid Pressure Sensor/Switch G Circuit Range/PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP083B relates to transmission fluid pressure sensor/switch g circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P083CTransmission Fluid Pressure Sensor/Switch G Circuit LowCheck soonTransmission Issues30–120 minutes for initial diagnosisP083C relates to transmission fluid pressure sensor/switch g circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P083DTransmission Fluid Pressure Sensor/Switch G Circuit HighCheck soonTransmission Issues30–120 minutes for initial diagnosisP083D relates to transmission fluid pressure sensor/switch g circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P083ETransmission Fluid Pressure Sensor/Switch G Circuit IntermittentCheck soonTransmission Issues30–120 minutes for initial diagnosisP083E relates to transmission fluid pressure sensor/switch g circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P083FClutch Pedal Switch A/B CorrelationCheck soonTransmission Issues30–120 minutes for initial diagnosisP083F relates to clutch pedal switch a/b correlation. Check the fault conditions and vehicle-specific procedure before replacing parts.P0840Transmission Fluid Pressure Sensor/Switch A CircuitCheck soonTransmission Issues30–120 minutes for initial diagnosisP0840 relates to transmission fluid pressure sensor/switch a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0841Transmission Fluid Pressure Sensor/Switch A Circuit Range/PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP0841 relates to transmission fluid pressure sensor/switch a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0842Transmission Fluid Pressure Sensor/Switch A Circuit LowCheck soonTransmission Issues30–120 minutes for initial diagnosisP0842 relates to transmission fluid pressure sensor/switch a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0843Transmission Fluid Pressure Sensor/Switch A Circuit HighCheck soonTransmission Issues30–120 minutes for initial diagnosisP0843 relates to transmission fluid pressure sensor/switch a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0844Transmission Fluid Pressure Sensor/Switch A Circuit IntermittentCheck soonTransmission Issues30–120 minutes for initial diagnosisP0844 relates to transmission fluid pressure sensor/switch a circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P0845Transmission Fluid Pressure Sensor/Switch B CircuitCheck soonTransmission Issues30–120 minutes for initial diagnosisP0845 relates to transmission fluid pressure sensor/switch b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0846Transmission Fluid Pressure Sensor/Switch B Circuit Range/PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP0846 relates to transmission fluid pressure sensor/switch b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0847Transmission Fluid Pressure Sensor/Switch B Circuit LowCheck soonTransmission Issues30–120 minutes for initial diagnosisP0847 relates to transmission fluid pressure sensor/switch b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0848Transmission Fluid Pressure Sensor/Switch B Circuit HighCheck soonTransmission Issues30–120 minutes for initial diagnosisP0848 relates to transmission fluid pressure sensor/switch b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0849Transmission Fluid Pressure Sensor/Switch B Circuit IntermittentCheck soonTransmission Issues30–120 minutes for initial diagnosisP0849 relates to transmission fluid pressure sensor/switch b circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P084ATransmission Fluid Pressure Sensor/Switch H CircuitCheck soonTransmission Issues30–120 minutes for initial diagnosisP084A relates to transmission fluid pressure sensor/switch h circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P084BTransmission Fluid Pressure Sensor/Switch H Circuit Range/PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP084B relates to transmission fluid pressure sensor/switch h circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P084CTransmission Fluid Pressure Sensor/Switch H Circuit LowCheck soonTransmission Issues30–120 minutes for initial diagnosisP084C relates to transmission fluid pressure sensor/switch h circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P084DTransmission Fluid Pressure Sensor/Switch H Circuit HighCheck soonTransmission Issues30–120 minutes for initial diagnosisP084D relates to transmission fluid pressure sensor/switch h circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P084ETransmission Fluid Pressure Sensor/Switch H Circuit IntermittentCheck soonTransmission Issues30–120 minutes for initial diagnosisP084E relates to transmission fluid pressure sensor/switch h circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P084FPark/Neutral Switch Output CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP084F relates to park/neutral switch output circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.