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

• P0619 — P0619 — Alternative Fuel Control Module RAM/ROM Error. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
• P061A — P061A — Internal Control Module Torque Performance. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: faulty sensor or actuator of the affected circuit, poor ground connection, control module driver fault.
• P061B — Internal Control Module Torque Calculation Performance (P061B): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by open or shorted wiring in the circuit, poor ground connection, faulty sensor or actuator of the affected circuit.
• P061C — P061C — Internal Control Module Engine RPM Performance. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: control module driver fault, corroded, loose or damaged connector, poor ground connection.
• P061D — P061D — Internal Control Module Engine Air Mass Performance. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: poor ground connection, corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit.
• P061E — OBD2 code P061E flags a problem with the ABS / stability control (internal control module brake signal performance). Short, gentle driving to a shop is usually possible. Common culprits: damaged tone (reluctor) ring on the hub, failed wheel speed sensor, faulty ABS module or pump motor.
• P061F — OBD2 code P061F flags a problem with the throttle and intake air metering (internal control module throttle actuator controller performance). Short, gentle driving to a shop is usually possible. Common culprits: dirty throttle body or stuck throttle plate, intake air leaks after the MAF sensor, contaminated or failed MAF/MAP sensor.
• P0620 — P0620 — Generator Control Circuit Malfunction. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: blown fuse feeding the circuit, control module driver fault, corroded, loose or damaged connector.
• P0621 — Generator Lamp "L" Control Circuit Malfunction (P0621): a powertrain (engine/transmission) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by poor ground connection, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
• P0622 — P0622 — Generator Field "F" Control Circuit Malfunction. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: corroded, loose or damaged connector, blown fuse feeding the circuit, poor ground connection.
• P0623 — OBD2 code P0623 flags a problem with the sensor and actuator circuits (generator lamp control circuit). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, corroded, loose or damaged connector, control module driver fault.
• P0624 — OBD2 code P0624 flags a problem with the evaporative emission (EVAP) system (fuel cap lamp control circuit). The car is usually drivable while you plan the repair. Common culprits: saturated or damaged charcoal canister, loose, damaged or wrong fuel cap, small leak in the fuel tank or filler neck.
• P0625 — OBD2 code P0625 flags a problem with the sensor and actuator circuits (generator field/f terminal circuit low). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, poor ground connection, open or shorted wiring in the circuit.
• P0626 — P0626 — Generator Field/F Terminal Circuit High. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: blown fuse feeding the circuit, open or shorted wiring in the circuit, control module driver fault.
• P0627 — P0627 — Fuel Pump "A" Control Circuit /Open. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: weak fuel pump or clogged fuel filter, faulty fuel pressure regulator, contaminated or incorrect fuel.
• P0628 — OBD2 code P0628 flags a problem with the fuel delivery and mixture control (fuel pump "A" control circuit low). Short, gentle driving to a shop is usually possible. Common culprits: faulty fuel rail pressure sensor or wiring, contaminated or incorrect fuel, weak fuel pump or clogged fuel filter.
• P0629 — OBD2 code P0629 flags a problem with the fuel delivery and mixture control (fuel pump "A" control circuit high). Short, gentle driving to a shop is usually possible. Common culprits: faulty fuel pressure regulator, vacuum or intake leaks skewing the mixture, clogged or leaking fuel injectors.
• P062A — OBD2 code P062A flags a problem with the fuel delivery and mixture control (fuel pump "A" control circuit range/performance). Short, gentle driving to a shop is usually possible. Common culprits: contaminated or incorrect fuel, clogged or leaking fuel injectors, vacuum or intake leaks skewing the mixture.
• P062B — OBD2 code P062B flags a problem with the fuel delivery and mixture control (internal control module fuel injector control performance). Short, gentle driving to a shop is usually possible. Common culprits: faulty fuel rail pressure sensor or wiring, vacuum or intake leaks skewing the mixture, clogged or leaking fuel injectors.
• P062C — P062C — Internal Control Module Vehicle Speed Performance. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: corroded, loose or damaged connector, poor ground connection, open or shorted wiring in the circuit.
• P062D — P062D — Fuel Injector Driver Circuit Performance Bank 1. A fault in the fuel delivery and mixture control. Short, gentle driving to a shop is usually possible. Typical causes: contaminated or incorrect fuel, faulty fuel rail pressure sensor or wiring, weak fuel pump or clogged fuel filter.
• P062E — OBD2 code P062E flags a problem with the fuel delivery and mixture control (fuel injector driver circuit performance bank 2). Short, gentle driving to a shop is usually possible. Common culprits: vacuum or intake leaks skewing the mixture, contaminated or incorrect fuel, faulty fuel pressure regulator.
• P062F — OBD2 code P062F flags a problem with the sensor and actuator circuits (internal control module EEPROM error). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, faulty sensor or actuator of the affected circuit, poor ground connection.
• P0630 — P0630 — VIN Not Programmed or Incompatible – ECM/PCM. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: poor ground connection, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.