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9,253 diagnostic guides

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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 625–648 of 1939

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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.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.P0850Park/Neutral Switch Input CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0850 relates to park/neutral switch input circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0851Park/Neutral Switch Input Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0851 relates to park/neutral switch input circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0852Park/Neutral Switch Input Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0852 relates to park/neutral switch input circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0853Drive Switch Input CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0853 relates to drive switch input circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0854Drive Switch Input Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0854 relates to drive switch input circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0855Drive Switch Input Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0855 relates to drive switch input circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0856Traction Control Input SignalCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0856 relates to traction control input signal. Check the fault conditions and vehicle-specific procedure before replacing parts.P0857Traction Control Input Signal Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0857 relates to traction control input signal range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0858Traction Control Input Signal LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0858 relates to traction control input signal low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0859Traction Control Input Signal HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0859 relates to traction control input signal high. Check the fault conditions and vehicle-specific procedure before replacing parts.P0863TCM Communication CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0863 relates to tcm communication circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P0864TCM Communication Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0864 relates to tcm communication circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0865TCM Communication Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0865 relates to tcm communication circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P0866TCM Communication Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0866 relates to tcm communication circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P086ANeutral Position Sensor A Circuit/OpenCheck soonSensors & Electronics30–120 minutes for initial diagnosisP086A relates to neutral position sensor a circuit/open. Check the fault conditions and vehicle-specific procedure before replacing parts.P086BNeutral Position Sensor A Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP086B relates to neutral position sensor a range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P086CNeutral Position Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP086C relates to neutral position sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P086DNeutral Position Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP086D relates to neutral position sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P086ENeutral Position Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP086E relates to neutral position sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P086FNeutral Position Sensor A Not LearnedCheck soonSensors & Electronics30–120 minutes for initial diagnosisP086F relates to neutral position sensor a not learned. Check the fault conditions and vehicle-specific procedure before replacing parts.P0880TCM Power Input SignalCheck soonSensors & Electronics30–120 minutes for initial diagnosisP0880 relates to tcm power input signal. Check the fault conditions and vehicle-specific procedure before replacing parts.