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

• P0051 — HO2S Heater Control Circuit Low (Bank 2 Sensor 1) (P0051): a powertrain (engine/transmission) fault affecting the oxygen sensor circuit. The car is usually drivable while you plan the repair. Most often caused by damaged sensor wiring or connector, oil or coolant contamination of the sensor tip, aged or contaminated oxygen sensor.
• P0052 — OBD2 code P0052 flags a problem with the oxygen sensor circuit (HO2S heater control circuit high (bank 2 sensor 1)). The car is usually drivable while you plan the repair. Common culprits: damaged sensor wiring or connector, aged or contaminated oxygen sensor, blown sensor heater fuse.
• P0053 — HO2S Heater Resistance (Bank 1, Sensor 1) (P0053): a powertrain (engine/transmission) fault affecting the oxygen sensor circuit. The car is usually drivable while you plan the repair. Most often caused by blown sensor heater fuse, aged or contaminated oxygen sensor, oil or coolant contamination of the sensor tip.
• P0054 — HO2S Heater Resistance (Bank 1, Sensor 2) (P0054): a powertrain (engine/transmission) fault affecting the oxygen sensor circuit. The car is usually drivable while you plan the repair. Most often caused by exhaust leak near the sensor, ECM signal circuit fault, aged or contaminated oxygen sensor.
• P0055 — OBD2 code P0055 flags a problem with the oxygen sensor circuit (HO2S heater resistance (bank 1, sensor 3)). The car is usually drivable while you plan the repair. Common culprits: damaged sensor wiring or connector, aged or contaminated oxygen sensor, oil or coolant contamination of the sensor tip.
• P0056 — P0056 — HO2S Heater Control Circuit (Bank 2 Sensor 2). A fault in the oxygen sensor circuit. The car is usually drivable while you plan the repair. Typical causes: damaged sensor wiring or connector, exhaust leak near the sensor, ECM signal circuit fault.
• P0057 — P0057 — HO2S Heater Control Circuit Low (Bank 2 Sensor 2). A fault in the oxygen sensor circuit. The car is usually drivable while you plan the repair. Typical causes: damaged sensor wiring or connector, blown sensor heater fuse, ECM signal circuit fault.
• P0058 — P0058 — HO2S Heater Control Circuit High (Bank 2 Sensor 2). A fault in the oxygen sensor circuit. The car is usually drivable while you plan the repair. Typical causes: ECM signal circuit fault, exhaust leak near the sensor, aged or contaminated oxygen sensor.
• P0059 — P0059 — HO2S Heater Resistance (Bank 2, Sensor 1). A fault in the oxygen sensor circuit. The car is usually drivable while you plan the repair. Typical causes: oil or coolant contamination of the sensor tip, exhaust leak near the sensor, damaged sensor wiring or connector.
• P005A — P005A — "B" Camshaft Profile Control Performance/Stuck Off Bank 1. A fault in the camshaft position and variable valve timing. Short, gentle driving to a shop is usually possible. Typical causes: damaged sensor wiring or reluctor ring, low or dirty engine oil affecting VVT, worn cam phaser.
• P005B — "B" Camshaft Profile Control Stuck On Bank 1 (P005B): a powertrain (engine/transmission) fault affecting the camshaft position and variable valve timing. Short, gentle driving to a shop is usually possible. Most often caused by stuck or clogged VVT oil control valve (OCV), faulty camshaft position sensor, worn cam phaser.
• P005C — P005C — "B" Camshaft Profile Control Performance/Stuck Off Bank 2. A fault in the camshaft position and variable valve timing. Short, gentle driving to a shop is usually possible. Typical causes: faulty camshaft position sensor, worn cam phaser, stuck or clogged VVT oil control valve (OCV).
• P005D — P005D — "B" Camshaft Profile Control Stuck On Bank 2. A fault in the camshaft position and variable valve timing. Short, gentle driving to a shop is usually possible. Typical causes: low or dirty engine oil affecting VVT, worn cam phaser, damaged sensor wiring or reluctor ring.
• P005E — Turbocharger/Supercharger Boost Control "B" Supply Voltage Circuit Low (P005E): a powertrain (engine/transmission) fault affecting the turbocharger / supercharger boost control. Short, gentle driving to a shop is usually possible. Most often caused by clogged intake or exhaust (DPF/cat), faulty boost pressure sensor, stuck wastegate or faulty boost control solenoid.
• P005F — OBD2 code P005F flags a problem with the turbocharger / supercharger boost control (turbocharger/supercharger boost control "B" supply voltage circuit high). Short, gentle driving to a shop is usually possible. Common culprits: faulty boost pressure sensor, stuck wastegate or faulty boost control solenoid, boost leak in intercooler piping or hoses.
• P0060 — P0060 — HO2S Heater Resistance (Bank 2, Sensor 2). A fault in the oxygen sensor circuit. The car is usually drivable while you plan the repair. Typical causes: damaged sensor wiring or connector, blown sensor heater fuse, exhaust leak near the sensor.
• P0061 — HO2S Heater Resistance (Bank 2, Sensor 3) (P0061): a powertrain (engine/transmission) fault affecting the oxygen sensor circuit. The car is usually drivable while you plan the repair. Most often caused by blown sensor heater fuse, oil or coolant contamination of the sensor tip, aged or contaminated oxygen sensor.
• P0062 — OBD2 code P0062 flags a problem with the oxygen sensor circuit (HO2S heater control circuit (bank 2 sensor 3)). The car is usually drivable while you plan the repair. Common culprits: damaged sensor wiring or connector, blown sensor heater fuse, ECM signal circuit fault.
• P0063 — HO2S Heater Control Circuit Low (Bank 2 Sensor 3) (P0063): a powertrain (engine/transmission) fault affecting the oxygen sensor circuit. The car is usually drivable while you plan the repair. Most often caused by blown sensor heater fuse, ECM signal circuit fault, oil or coolant contamination of the sensor tip.
• P0064 — OBD2 code P0064 flags a problem with the oxygen sensor circuit (HO2S heater control circuit high (bank 2 sensor 3)). The car is usually drivable while you plan the repair. Common culprits: oil or coolant contamination of the sensor tip, aged or contaminated oxygen sensor, blown sensor heater fuse.
• P0065 — P0065 — Air Assisted Injector Control Range/Performance. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: vacuum or intake leaks skewing the mixture, clogged or leaking fuel injectors, contaminated or incorrect fuel.
• P0066 — OBD2 code P0066 flags a problem with the fuel delivery and mixture control (air assisted injector control circuit or circuit low). Short, gentle driving to a shop is usually possible. Common culprits: weak fuel pump or clogged fuel filter, faulty fuel rail pressure sensor or wiring, clogged or leaking fuel injectors.
• P0067 — P0067 — Air Assisted Injector Control Circuit High. 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, faulty fuel pressure regulator, clogged or leaking fuel injectors.
• P0068 — OBD2 code P0068 flags a problem with the throttle and intake air metering (MAP/MAF - throttle position correlation). Short, gentle driving to a shop is usually possible. Common culprits: failed electronic throttle motor, faulty throttle position sensor or pedal sensor, contaminated or failed MAF/MAP sensor.