Diagnostic library

Find an OBD2 code

Search the code from your scanner, then narrow the library by system, severity, or code family.

9,253 diagnostic guides

Sort

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.

Check soon P · Powertrain Clear all

Quick browse

Choose a vehicle system

Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

FiltersSeverity · family

Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

Vehicle coverage

These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.

Diagnostic codes

Showing 1705–1728 of 6682

Most searched first

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.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.P085AGear Shift Control Module B Communication CircuitCheck soonTransmission Issues30–120 minutes for initial diagnosisP085A relates to gear shift control module b communication circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P085BGear Shift Control Module B Communication Circuit LowCheck soonTransmission Issues30–120 minutes for initial diagnosisP085B relates to gear shift control module b communication circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P085CGear Shift Control Module B Communication Circuit HighCheck soonTransmission Issues30–120 minutes for initial diagnosisP085C relates to gear shift control module b communication circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P085DGear Shift Control Module A PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP085D relates to gear shift control module a performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P085EGear Shift Control Module B PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP085E relates to gear shift control module b performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P085FUp and Down Shift Switch Circuit Range/PerformanceCheck soonTransmission Issues30–120 minutes for initial diagnosisP085F relates to up and down shift switch circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P0860Gear Shift Control Module A Communication CircuitCheck soonTransmission Issues30–120 minutes for initial diagnosisP0860 relates to gear shift control module a communication circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.