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

• C1767 — C1767 — Air Suspension Rear Height Sensor Low Signal Circuit Short To Battery. 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.
• C1768 — OBD2 code C1768 flags a problem with the sensor and actuator circuits (air suspension rear height sensor low signal circuit short to ground). The car is usually drivable while you plan the repair. Common culprits: open or shorted wiring in the circuit, blown fuse feeding the circuit, corroded, loose or damaged connector.
• C1770 — OBD2 code C1770 flags a problem with the sensor and actuator circuits (air suspension vent solenoid output circuit failure). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, control module driver fault, open or shorted wiring in the circuit.
• C1771 — OBD2 code C1771 flags a problem with the sensor and actuator circuits (air suspension vent solenoid output circuit open). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, poor ground connection, faulty sensor or actuator of the affected circuit.
• C1772 — OBD2 code C1772 flags a problem with the sensor and actuator circuits (air suspension vent solenoid output circuit short to battery). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, poor ground connection, control module driver fault.
• C1773 — Air Suspension Vent Solenoid Output Circuit Short To Ground (C1773): 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, control module driver fault, faulty sensor or actuator of the affected circuit.
• C1774 — C1774 — Coolant Temp Out of Range. A fault in the engine cooling and temperature control. Short, gentle driving to a shop is usually possible. Typical causes: failed cooling fan or fan relay, water pump or radiator issues, wiring faults in the sensor circuit.
• C1775 — OBD2 code C1775 flags a problem with the sensor and actuator circuits (DC-DC converter failure). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, control module driver fault, open or shorted wiring in the circuit.
• C1776 — OBD2 code C1776 flags a problem with the sensor and actuator circuits (heater system failure). 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, open or shorted wiring in the circuit.
• C1777 — OBD2 code C1777 flags a problem with the sensor and actuator circuits (vacuum pressure circuit failure). The car is usually drivable while you plan the repair. Common culprits: control module driver fault, blown fuse feeding the circuit, faulty sensor or actuator of the affected circuit.
• C1778 — Power Steering Failure (C1778): 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 open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector.
• C1779 — C1779 — Blower Switch Failure. 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, poor ground connection.
• C1780 — OBD2 code C1780 flags a problem with the sensor and actuator circuits (temperature select failure). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit.
• C1781 — C1781 — Engine Coolant Temperature Signal Missing/Fault. A fault in the engine cooling and temperature control. Short, gentle driving to a shop is usually possible. Typical causes: low coolant level or air in the system, thermostat stuck open or closed, water pump or radiator issues.
• C1790 — Air Suspension LR Air Spring/Shock Solenoid Output Circuit Failure (C1790): 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, blown fuse feeding the circuit.
• C1791 — OBD2 code C1791 flags a problem with the sensor and actuator circuits (air suspension LR air spring/shock solenoid output circuit open). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, control module driver fault, poor ground connection.
• C1792 — Air Suspension LR Air Spring/Shock Solenoid Output Circuit Short To Battery (C1792): 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, blown fuse feeding the circuit, control module driver fault.
• C1793 — Air Suspension LR Air Spring/Shock Solenoid Output Circuit Short To Ground (C1793): 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 corroded, loose or damaged connector, open or shorted wiring in the circuit, poor ground connection.
• C1795 — C1795 — Air Suspension RR Air Spring/Shock Solenoid Output Circuit Failure. 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, corroded, loose or damaged connector.
• C1796 — OBD2 code C1796 flags a problem with the sensor and actuator circuits (air suspension RR air spring/shock solenoid output circuit open). The car is usually drivable while you plan the repair. Common culprits: control module driver fault, faulty sensor or actuator of the affected circuit, blown fuse feeding the circuit.
• C1797 — Air Suspension RR Air Spring/Shock Solenoid Output Circuit Short To Battery (C1797): 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, corroded, loose or damaged connector, open or shorted wiring in the circuit.
• C1798 — Air Suspension RR Air Spring/Shock Solenoid Output Circuit Short To Ground (C1798): 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, poor ground connection, open or shorted wiring in the circuit.
• C1800 — C1800 — Air Suspension Reservoir Solenoid Circuit 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, poor ground connection, corroded, loose or damaged connector.
• C1805 — Mismatched PCM and/or ABS-TC Module (C1805): a chassis (brakes/steering/suspension) fault affecting the ABS / stability control. Short, gentle driving to a shop is usually possible. Most often caused by faulty ABS module or pump motor, damaged tone (reluctor) ring on the hub, failed wheel speed sensor.