OBD2 Fault Code Library
Free lookup for thousands of OBD2 trouble codes: filter by family, read short meanings, and open deeper articles. Desktop ELM327 scanner with live data and AI guidance.
OBD2 symptoms
Look up diagnostic trouble codes by what the car is doing: misfire, overheating, rough idle, a check engine light, and other common symptoms.
- Engine misfire
- Engine overheating
- Rough idle
- Check engine light
- Poor fuel economy
- Hard starting
- Engine stalling
- Catalytic converter efficiency
- Oxygen sensor fault
- EVAP leak
- Thermostat not reaching temperature
- Lean air-fuel mixture
- Rich air-fuel mixture
- EGR flow fault
- Engine knock
- Charging system
- Throttle position
- Mass airflow sensor
- Turbo underboost
- Coolant temperature sensor
- Transmission fault
- P0456 — OBD2 code P0456 flags a problem with the evaporative emission (EVAP) system (evaporative emissions system small leak detected). The car is usually drivable while you plan the repair. Common culprits: faulty purge valve (canister purge solenoid), small leak in the fuel tank or filler neck, faulty vent valve or leak detection pump.
- P0457 — P0457 — Evaporative Emission Control System Leak Detected. A fault in the evaporative emission (EVAP) system. The car is usually drivable while you plan the repair. Typical causes: faulty vent valve or leak detection pump, small leak in the fuel tank or filler neck, faulty purge valve (canister purge solenoid).
- P0458 — Evaporative Emission System Purge Control Valve Circuit Low (P0458): a powertrain (engine/transmission) fault affecting the evaporative emission (EVAP) system. The car is usually drivable while you plan the repair. Most often caused by small leak in the fuel tank or filler neck, cracked EVAP hoses or lines, faulty purge valve (canister purge solenoid).
- P0459 — P0459 — Evaporative Emission System Purge Control Valve Circuit High. A fault in the evaporative emission (EVAP) system. The car is usually drivable while you plan the repair. Typical causes: saturated or damaged charcoal canister, faulty purge valve (canister purge solenoid), faulty vent valve or leak detection pump.
- P045A — P045A — Exhaust Gas Recirculation "B" Control Circuit. A fault in the exhaust gas recirculation (EGR) system. The car is usually drivable while you plan the repair. Typical causes: vacuum leaks in EGR control lines, failed EGR valve or position sensor, ECM control circuit fault.
- P045B — Exhaust Gas Recirculation "B" Control Circuit Range/Performance (P045B): a powertrain (engine/transmission) fault affecting the exhaust gas recirculation (EGR) system. The car is usually drivable while you plan the repair. Most often caused by carbon buildup blocking the EGR valve or passages, vacuum leaks in EGR control lines, ECM control circuit fault.
- P045C — OBD2 code P045C flags a problem with the exhaust gas recirculation (EGR) system (exhaust gas recirculation "B" control circuit low). The car is usually drivable while you plan the repair. Common culprits: ECM control circuit fault, vacuum leaks in EGR control lines, faulty EGR solenoid or wiring.
- P045D — OBD2 code P045D flags a problem with the exhaust gas recirculation (EGR) system (exhaust gas recirculation "B" control circuit high). The car is usually drivable while you plan the repair. Common culprits: ECM control circuit fault, failed EGR valve or position sensor, carbon buildup blocking the EGR valve or passages.
- P045E — Exhaust Gas Recirculation "B" Control Stuck Open (P045E): a powertrain (engine/transmission) fault affecting the exhaust gas recirculation (EGR) system. The car is usually drivable while you plan the repair. Most often caused by failed EGR valve or position sensor, vacuum leaks in EGR control lines, faulty EGR solenoid or wiring.
- P045F — Exhaust Gas Recirculation "B" Control Stuck Closed (P045F): a powertrain (engine/transmission) fault affecting the exhaust gas recirculation (EGR) system. The car is usually drivable while you plan the repair. Most often caused by faulty EGR solenoid or wiring, ECM control circuit fault, failed EGR valve or position sensor.
- P0460 — OBD2 code P0460 flags a problem with the fuel delivery and mixture control (fuel level sensor circuit malfunction). Short, gentle driving to a shop is usually possible. Common culprits: clogged or leaking fuel injectors, faulty fuel rail pressure sensor or wiring, contaminated or incorrect fuel.
- P0461 — P0461 — Fuel Level Sensor Circuit Range/Performance. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: faulty fuel rail pressure sensor or wiring, clogged or leaking fuel injectors, faulty fuel pressure regulator.
- P0462 — P0462 — Fuel Level Sensor Circuit Low Input. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: faulty fuel pressure regulator, contaminated or incorrect fuel, vacuum or intake leaks skewing the mixture.
- P0463 — OBD2 code P0463 flags a problem with the fuel delivery and mixture control (fuel level sensor circuit high input). Short, gentle driving to a shop is usually possible. Common culprits: faulty fuel pressure regulator, vacuum or intake leaks skewing the mixture, weak fuel pump or clogged fuel filter.
- P0464 — Fuel Level Sensor Circuit Intermittent (P0464): a powertrain (engine/transmission) fault affecting the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Most often caused by contaminated or incorrect fuel, vacuum or intake leaks skewing the mixture, faulty fuel pressure regulator.
- P0465 — Purge Flow Sensor Circuit Malfunction (P0465): a powertrain (engine/transmission) fault affecting the evaporative emission (EVAP) system. The car is usually drivable while you plan the repair. Most often caused by faulty vent valve or leak detection pump, cracked EVAP hoses or lines, faulty purge valve (canister purge solenoid).
- P0466 — Purge Flow Sensor Circuit Range/Performance (P0466): a powertrain (engine/transmission) fault affecting the evaporative emission (EVAP) system. The car is usually drivable while you plan the repair. Most often caused by small leak in the fuel tank or filler neck, cracked EVAP hoses or lines, faulty purge valve (canister purge solenoid).
- P0467 — Purge Flow Sensor Circuit Low Input (P0467): a powertrain (engine/transmission) fault affecting the evaporative emission (EVAP) system. The car is usually drivable while you plan the repair. Most often caused by cracked EVAP hoses or lines, faulty vent valve or leak detection pump, loose, damaged or wrong fuel cap.
- P0468 — Purge Flow Sensor Circuit High Input (P0468): a powertrain (engine/transmission) fault affecting the evaporative emission (EVAP) system. The car is usually drivable while you plan the repair. Most often caused by cracked EVAP hoses or lines, saturated or damaged charcoal canister, faulty vent valve or leak detection pump.
- P0469 — Purge Flow Sensor Circuit Intermittent (P0469): a powertrain (engine/transmission) fault affecting the evaporative emission (EVAP) system. The car is usually drivable while you plan the repair. Most often caused by loose, damaged or wrong fuel cap, faulty vent valve or leak detection pump, saturated or damaged charcoal canister.
- P046A — P046A — Catalyst Temperature Sensor 1/2 Correlation (Bank 1). A fault in the catalytic converter efficiency monitoring. The car is usually drivable while you plan the repair. Typical causes: exhaust leak ahead of the converter, persistent rich or lean fuel mixture, oil or coolant entering the exhaust.
- P046B — OBD2 code P046B flags a problem with the catalytic converter efficiency monitoring (catalyst temperature sensor 1/2 correlation (bank 2)). The car is usually drivable while you plan the repair. Common culprits: engine misfires damaging the catalyst, exhaust leak ahead of the converter, aged or contaminated catalytic converter.
- P046C — Exhaust Gas Recirculation Sensor "A" Circuit Range/Performance (P046C): a powertrain (engine/transmission) fault affecting the exhaust gas recirculation (EGR) system. The car is usually drivable while you plan the repair. Most often caused by faulty EGR solenoid or wiring, carbon buildup blocking the EGR valve or passages, failed EGR valve or position sensor.
- P046D — P046D — Exhaust Gas Recirculation Sensor "A" Circuit Intermittent/Erratic. A fault in the exhaust gas recirculation (EGR) system. The car is usually drivable while you plan the repair. Typical causes: vacuum leaks in EGR control lines, faulty EGR solenoid or wiring, failed EGR valve or position sensor.