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

• C1715 — OBD2 code C1715 flags a problem with the sensor and actuator circuits (right front sensor circuit failure). The car is usually drivable while you plan the repair. Common culprits: poor ground connection, blown fuse feeding the circuit, open or shorted wiring in the circuit.
• C1716 — C1716 — Right Front Sensor Circuit Fault. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: open or shorted wiring in the circuit, blown fuse feeding the circuit, faulty sensor or actuator of the affected circuit.
• C1717 — OBD2 code C1717 flags a problem with the sensor and actuator circuits (left front center sensor circuit short to vbat). The car is usually drivable while you plan the repair. Common culprits: poor ground connection, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
• C1718 — Left Front Center Sensor Circuit Failure (C1718): a chassis (brakes/steering/suspension) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by control module driver fault, open or shorted wiring in the circuit, blown fuse feeding the circuit.
• C1719 — C1719 — Left Front Center Sensor Circuit Fault. 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, corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit.
• C1721 — C1721 — Air Suspension Height Sensor Power Circuit Open. 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, blown fuse feeding the circuit.
• C1722 — OBD2 code C1722 flags a problem with the sensor and actuator circuits (air suspension height sensor power circuit short to battery). The car is usually drivable while you plan the repair. Common culprits: control module driver fault, faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector.
• C1723 — Air Suspension Height Sensor Power Circuit Short To Ground (C1723): a chassis (brakes/steering/suspension) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by blown fuse feeding the circuit, faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector.
• C1724 — OBD2 code C1724 flags a problem with the sensor and actuator circuits (air suspension height sensor power circuit failure). The car is usually drivable while you plan the repair. Common culprits: open or shorted wiring in the circuit, blown fuse feeding the circuit, control module driver fault.
• C1725 — C1725 — Air Suspension Front Pneumatic Failure. 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, open or shorted wiring in the circuit.
• C1726 — C1726 — Air Suspension Rear Pneumatic Failure. 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, open or shorted wiring in the circuit.
• C1727 — C1727 — Air Suspension Reservoir Pneumatic Failure. 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, control module driver fault, blown fuse feeding the circuit.
• C1728 — Transfer Case unable to transition between 2H and 4H (C1728): a chassis (brakes/steering/suspension) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by blown fuse feeding the circuit, faulty sensor or actuator of the affected circuit, open or shorted wiring in the circuit.
• C1729 — Transfer Case unable to transition between 4H and 4L (C1729): a chassis (brakes/steering/suspension) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by poor ground connection, corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit.
• C1730 — Reference Voltage Out of Range (+5 v) (C1730): a chassis (brakes/steering/suspension) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by poor ground connection, blown fuse feeding the circuit, control module driver fault.
• C1731 — OBD2 code C1731 flags a problem with the sensor and actuator circuits (air suspension LF corner up timeout). The car is usually drivable while you plan the repair. Common culprits: poor ground connection, corroded, loose or damaged connector, blown fuse feeding the circuit.
• C1732 — C1732 — Air Suspension LF Corner Down Timeout. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: control module driver fault, blown fuse feeding the circuit, faulty sensor or actuator of the affected circuit.
• C1733 — C1733 — Air Suspension RF Corner Up Timeout. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: poor ground connection, open or shorted wiring in the circuit, control module driver fault.
• C1734 — C1734 — Air Suspension RF Corner Down Timeout. 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, poor ground connection.
• C1735 — OBD2 code C1735 flags a problem with the sensor and actuator circuits (air suspension LR corner up timeout). 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.
• C1736 — OBD2 code C1736 flags a problem with the sensor and actuator circuits (air suspension LR corner down timeout). The car is usually drivable while you plan the repair. Common culprits: poor ground connection, control module driver fault, corroded, loose or damaged connector.
• C1737 — C1737 — Air Suspension RR Corner Up Timeout. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: poor ground connection, open or shorted wiring in the circuit, control module driver fault.
• C1738 — Air Suspension RR Corner Down Timeout (C1738): a chassis (brakes/steering/suspension) fault affecting the sensor and actuator circuits. The car is usually drivable while you plan the repair. Most often caused by faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector, control module driver fault.
• C1739 — OBD2 code C1739 flags a problem with the sensor and actuator circuits (right front center sensor circuit short to vbat). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit.