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

• C1813 — OBD2 code C1813 flags a problem with the sensor and actuator circuits (air suspension LR vent request exceeded max timing). 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.
• C1814 — OBD2 code C1814 flags a problem with the sensor and actuator circuits (air suspension RR vent request exceeded max timing). 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, control module driver fault.
• C1818 — OBD2 code C1818 flags a problem with the sensor and actuator circuits (air suspension LR air compress request exceeded max timing). The car is usually drivable while you plan the repair. Common culprits: blown fuse feeding the circuit, control module driver fault, faulty sensor or actuator of the affected circuit.
• C1819 — C1819 — Air Suspension RR Air Compress Request Exceeded Max Timing. 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.
• C1820 — OBD2 code C1820 flags a problem with the sensor and actuator circuits (air suspension RF air compress request exceeded max timing). The car is usually drivable while you plan the repair. Common culprits: faulty sensor or actuator of the affected circuit, poor ground connection, control module driver fault.
• C1830 — C1830 — Air Suspension Compressor Relay Circuit Failure. 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, control module driver fault.
• C1831 — C1831 — Air Suspension Compressor Relay Circuit Open. 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, control module driver fault.
• C1832 — C1832 — Air Suspension Compressor Relay Circuit Short To Battery. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: control module driver fault, faulty sensor or actuator of the affected circuit, blown fuse feeding the circuit.
• C1833 — OBD2 code C1833 flags a problem with the sensor and actuator circuits (air suspension compressor relay circuit short to ground). The car is usually drivable while you plan the repair. Common culprits: control module driver fault, open or shorted wiring in the circuit, corroded, loose or damaged connector.
• C1834 — C1834 — Gauge Drive Current Fault. A fault in the sensor and actuator circuits. The car is usually drivable while you plan the repair. Typical causes: control module driver fault, faulty sensor or actuator of the affected circuit, blown fuse feeding the circuit.
• C1835 — Current Sense Circuit Failure (C1835): 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, poor ground connection, control module driver fault.
• C1836 — Battery Temp out of Range (C1836): 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, control module driver fault, blown fuse feeding the circuit.
• C1837 — C1837 — Battery Heater Circuit 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, faulty sensor or actuator of the affected circuit, corroded, loose or damaged connector.
• C1838 — Charging System Fault (C1838): 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, open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit.
• C1839 — OBD2 code C1839 flags a problem with the sensor and actuator circuits (leakage fault). The car is usually drivable while you plan the repair. Common culprits: open or shorted wiring in the circuit, corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit.
• C1840 — OBD2 code C1840 flags a problem with the sensor and actuator circuits (air suspension disable switch circuit failure). The car is usually drivable while you plan the repair. Common culprits: open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit, control module driver fault.
• C1841 — OBD2 code C1841 flags a problem with the sensor and actuator circuits (air suspension disable switch circuit open). The car is usually drivable while you plan the repair. Common culprits: poor ground connection, blown fuse feeding the circuit, control module driver fault.
• C1842 — C1842 — Air Suspension Disable Switch Circuit Short To Battery. 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, control module driver fault, blown fuse feeding the circuit.
• C1843 — Air Suspension Disable Switch Circuit Short To Ground (C1843): 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, control module driver fault.
• C1844 — OBD2 code C1844 flags a problem with the sensor and actuator circuits (air suspension secondary front inflator solenoid output circuit failure). The car is usually drivable while you plan the repair. Common culprits: faulty sensor or actuator of the affected circuit, poor ground connection, corroded, loose or damaged connector.
• C1845 — Air Suspension Front Inflator Solenoid Output Circuit Failure (C1845): 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, blown fuse feeding the circuit, corroded, loose or damaged connector.
• C1846 — OBD2 code C1846 flags a problem with the sensor and actuator circuits (air suspension front inflator solenoid output circuit open). The car is usually drivable while you plan the repair. Common culprits: open or shorted wiring in the circuit, corroded, loose or damaged connector, faulty sensor or actuator of the affected circuit.
• C1847 — OBD2 code C1847 flags a problem with the sensor and actuator circuits (air suspension front inflator solenoid output circuit short to battery). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, blown fuse feeding the circuit, open or shorted wiring in the circuit.
• C1848 — OBD2 code C1848 flags a problem with the sensor and actuator circuits (air suspension front inflator solenoid output circuit short to ground). The car is usually drivable while you plan the repair. Common culprits: faulty sensor or actuator of the affected circuit, poor ground connection, control module driver fault.