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.

Sensors & Electronics Check soon 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 745–768 of 1939

Most searched first

P202DReductant LeakageCheck soonSensors & Electronics30–120 minutes for initial diagnosisP202D relates to reductant leakage. Check the fault conditions and vehicle-specific procedure before replacing parts.P202FReductant/Regeneration Supply Control Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP202F relates to reductant/regeneration supply control circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P203AReductant Level Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203A relates to reductant level sensor a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P203BReductant Level Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203B relates to reductant level sensor a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P203CReductant Level Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203C relates to reductant level sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P203DReductant Level Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203D relates to reductant level sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P203EReductant Level Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203E relates to reductant level sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P203FReductant Level Too LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP203F relates to reductant level too low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2042Reductant Temperature Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2042 relates to reductant temperature sensor a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2043Reductant Temperature Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2043 relates to reductant temperature sensor a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2044Reductant Temperature Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2044 relates to reductant temperature sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2045Reductant Temperature Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2045 relates to reductant temperature sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2046Reductant Temperature Sensor A Circuit IntermittentCheck soonSensors & Electronics30–120 minutes for initial diagnosisP2046 relates to reductant temperature sensor a circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.P204AReductant Pressure Sensor CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP204A relates to reductant pressure sensor circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P204BReductant Pressure Sensor Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP204B relates to reductant pressure sensor circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P204CReductant Pressure Sensor Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP204C relates to reductant pressure sensor circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P204DReductant Pressure Sensor Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP204D relates to reductant pressure sensor circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P204EReductant Pressure Sensor Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP204E relates to reductant pressure sensor circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.P204FReductant System Performance Bank 1Check soonSensors & Electronics30–120 minutes for initial diagnosisP204F relates to reductant system performance bank 1. Check the fault conditions and vehicle-specific procedure before replacing parts.P205AReductant Tank Temperature Sensor A CircuitCheck soonSensors & Electronics30–120 minutes for initial diagnosisP205A relates to reductant tank temperature sensor a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P205BReductant Tank Temperature Sensor A Circuit Range/PerformanceCheck soonSensors & Electronics30–120 minutes for initial diagnosisP205B relates to reductant tank temperature sensor a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P205CReductant Tank Temperature Sensor A Circuit LowCheck soonSensors & Electronics30–120 minutes for initial diagnosisP205C relates to reductant tank temperature sensor a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P205DReductant Tank Temperature Sensor A Circuit HighCheck soonSensors & Electronics30–120 minutes for initial diagnosisP205D relates to reductant tank temperature sensor a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P205EReductant Tank Temperature Sensor A Circuit Intermittent/ErraticCheck soonSensors & Electronics30–120 minutes for initial diagnosisP205E relates to reductant tank temperature sensor a circuit intermittent/erratic. Check the fault conditions and vehicle-specific procedure before replacing parts.