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.

Low priority 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 217–240 of 298

Most searched first

P2516A/C Refrigerant Pressure Sensor B Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2516 relates to a/c refrigerant pressure sensor b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2517A/C Refrigerant Pressure Sensor B Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2517 relates to a/c refrigerant pressure sensor b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2518A/C Refrigerant Pressure Sensor B Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2518 relates to a/c refrigerant pressure sensor b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2519A/C Request A CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2519 relates to a/c request a circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2520A/C Request A Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2520 relates to a/c request a circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2521A/C Request A Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2521 relates to a/c request a circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P2522A/C Request B CircuitLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2522 relates to a/c request b circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P2523A/C Request B Circuit LowLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2523 relates to a/c request b circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P2524A/C Request B Circuit HighLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2524 relates to a/c request b circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P255FA/C Request A Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP255F relates to a/c request a circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2561A/C Control Module Requested MIL IlluminationLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2561 relates to a/c control module requested mil illumination. Check the fault conditions and vehicle-specific procedure before replacing parts.P256FA/C Request B Circuit Range/PerformanceLow prioritySensors & Electronics30–120 minutes for initial diagnosisP256F relates to a/c request b circuit range/performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P2577Direct Ozone Reduction Catalyst Efficiency Below ThresholdLow priorityEmissions System30–120 minutes for initial diagnosisP2577 relates to direct ozone reduction catalyst efficiency below threshold. Check the fault conditions and vehicle-specific procedure before replacing parts.P2583Cruise Control Front Distance Range Sensor Single Sensor or CenterLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2583 relates to cruise control front distance range sensor single sensor or center. Check the fault conditions and vehicle-specific procedure before replacing parts.P2591Cruise Control Front Distance Range Sensor LeftLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2591 relates to cruise control front distance range sensor left. Check the fault conditions and vehicle-specific procedure before replacing parts.P2592Cruise Control Front Distance Range Sensor RightLow prioritySensors & Electronics30–120 minutes for initial diagnosisP2592 relates to cruise control front distance range sensor right. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B0Fuel Level Sensor A StuckLow priorityFuel System30–120 minutes for initial diagnosisP25B0 relates to fuel level sensor a stuck. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B1Fuel Level Sensor B StuckLow priorityFuel System30–120 minutes for initial diagnosisP25B1 relates to fuel level sensor b stuck. Check the fault conditions and vehicle-specific procedure before replacing parts.P25B2Fuel Level Sensor A or B StuckLow priorityFuel System30–120 minutes for initial diagnosisP25B2 relates to fuel level sensor a or b stuck. Check the fault conditions and vehicle-specific procedure before replacing parts.P25D7Fuel Level Sensor C CircuitLow priorityFuel System30–120 minutes for initial diagnosisP25D7 relates to fuel level sensor c circuit. Check the fault conditions and vehicle-specific procedure before replacing parts.P25D8Fuel Level Sensor C PerformanceLow priorityFuel System30–120 minutes for initial diagnosisP25D8 relates to fuel level sensor c performance. Check the fault conditions and vehicle-specific procedure before replacing parts.P25D9Fuel Level Sensor C Circuit LowLow priorityFuel System30–120 minutes for initial diagnosisP25D9 relates to fuel level sensor c circuit low. Check the fault conditions and vehicle-specific procedure before replacing parts.P25DAFuel Level Sensor C Circuit HighLow priorityFuel System30–120 minutes for initial diagnosisP25DA relates to fuel level sensor c circuit high. Check the fault conditions and vehicle-specific procedure before replacing parts.P25DBFuel Level Sensor C Circuit IntermittentLow priorityFuel System30–120 minutes for initial diagnosisP25DB relates to fuel level sensor c circuit intermittent. Check the fault conditions and vehicle-specific procedure before replacing parts.