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

• C1298 — C1298 — Rear Right Wheel Speed Signal Fault: Causes, Symptoms & Fix (C1298): a vehicle fault affecting the ABS / stability control. Short, gentle driving to a shop is usually possible. Most often caused by damaged tone (reluctor) ring on the hub, faulty ABS module or pump motor, blown fuse or low voltage to the ABS module.
• C1299 — OBD2 code C1299 flags a problem with the ABS / stability control (C1299 — rear left wheel speed signal fault: causes, symptoms & fix). Short, gentle driving to a shop is usually possible. Common culprits: blown fuse or low voltage to the ABS module, damaged tone (reluctor) ring on the hub, damaged sensor wiring or corroded connector.
• C1300 — OBD2 code C1300 flags a problem with the ABS / stability control (C1300 — ABS pump motor circuit failure: causes, symptoms & fix). Short, gentle driving to a shop is usually possible. Common culprits: faulty ABS module or pump motor, blown fuse or low voltage to the ABS module, damaged sensor wiring or corroded connector.
• C1301 — OBD2 code C1301 flags a problem with the ABS / stability control (C1301 — ABS operation timed out: causes, symptoms & fix). Short, gentle driving to a shop is usually possible. Common culprits: damaged tone (reluctor) ring on the hub, damaged sensor wiring or corroded connector, failed wheel speed sensor.
• C1302 — C1302 — Left Front Isolation Clamping Circuit Failure: Causes, Symptoms & Fix (C1302): a vehicle 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.
• C1303 — C1303 — Right Front Isolation Clamping Circuit Failure: Causes, Symptoms & Fix (C1303): a vehicle 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, poor ground connection.
• C1304 — OBD2 code C1304 flags a problem with the sensor and actuator circuits (C1304 — left rear isolation clamping circuit failure: causes, symptoms & fix). The car is usually drivable while you plan the repair. Common culprits: control module driver fault, open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit.
• C1305 — C1305 — Right Rear Isolation Clamping Circuit Failure: Causes, Symptoms & Fix (C1305): a vehicle 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, control module driver fault.
• C1306 — C1306 — Steering Wheel Angle No Center Found During Initialisation: Causes, Symptoms & Fix (C1306): a vehicle 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, open or shorted wiring in the circuit.
• C1307 — C1307 — C1307 — Steering Wheel Angle Sensor Encoder Ring Defective: Causes, Symptoms & Fix. 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, corroded, loose or damaged connector, poor ground connection.
• C1308 — C1308 — Front Axle Precharge Solenoid Valve Circuit Failure: Causes, Symptoms & Fix (C1308): a vehicle 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, control module driver fault.
• C1309 — C1309 — Rear Axle Precharge Solenoid Valve Circuit Failure: Causes, Symptoms & Fix (C1309): a vehicle 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.
• C1310 — C1310 — C1310 — Front Axle Switchover Valve Circuit Failure: Causes, Symptoms & Fix. 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, corroded, loose or damaged connector, blown fuse feeding the circuit.
• C1311 — C1311 — Rear Axle Switchover Valve Circuit Failure: Causes, Symptoms & Fix (C1311): a vehicle 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, control module driver fault.
• C1312 — C1312 — C1312 — Master Brake Cylinder Switchover Valve: Causes, Symptoms & Fix. A fault in the ABS / stability control. Short, gentle driving to a shop is usually possible. Typical causes: faulty ABS module or pump motor, failed wheel speed sensor, damaged tone (reluctor) ring on the hub.
• C1313 — OBD2 code C1313 flags a problem with the ABS / stability control (C1313 — ABS solenoid valve relay circuit failure: causes, symptoms & fix). Short, gentle driving to a shop is usually possible. Common culprits: damaged tone (reluctor) ring on the hub, damaged sensor wiring or corroded connector, blown fuse or low voltage to the ABS module.
• C1314 — OBD2 code C1314 flags a problem with the ABS / stability control (C1314 — ABS solenoid valve relay voltage supply: causes, symptoms & fix). Short, gentle driving to a shop is usually possible. Common culprits: blown fuse or low voltage to the ABS module, failed wheel speed sensor, damaged sensor wiring or corroded connector.
• C1315 — C1315 — C1315 — ABS Inlet Solenoid Valve Voltage Supply: Causes, Symptoms & Fix. A fault in the ABS / stability control. Short, gentle driving to a shop is usually possible. Typical causes: failed wheel speed sensor, faulty ABS module or pump motor, damaged sensor wiring or corroded connector.
• C1332 — C1332 — ABS Outlet Valve Coil LF Circuit Excessive Temperature: Causes, Symptoms & Fix (C1332): a vehicle fault affecting the ignition system. Short, gentle driving to a shop is usually possible. Most often caused by worn spark plugs or wrong plug gap, damaged coil wiring or connector, moisture or oil in the spark plug wells.
• C1333 — C1333 — C1333 — ABS Inlet Valve Coil LR Circuit Excessive Temperature: Causes, Symptoms & Fix. A fault in the ignition system. Short, gentle driving to a shop is usually possible. Typical causes: failed ignition coil or coil pack, faulty ignition control circuit in the ECM, worn spark plugs or wrong plug gap.
• C1334 — OBD2 code C1334 flags a problem with the ignition system (C1334 — ABS inlet valve coil LF circuit excessive temperature: causes, symptoms & fix). Short, gentle driving to a shop is usually possible. Common culprits: damaged coil wiring or connector, worn spark plugs or wrong plug gap, moisture or oil in the spark plug wells.
• C1335 — OBD2 code C1335 flags a problem with the ignition system (C1335 — ABS inlet valve coil RF circuit excessive temperature: causes, symptoms & fix). Short, gentle driving to a shop is usually possible. Common culprits: faulty ignition control circuit in the ECM, moisture or oil in the spark plug wells, worn spark plugs or wrong plug gap.
• C1336 — C1336 — C1336 — ABS Inlet Valve Coil RR Circuit Excessive Temperature: Causes, Symptoms & Fix. A fault in the ignition system. Short, gentle driving to a shop is usually possible. Typical causes: moisture or oil in the spark plug wells, damaged coil wiring or connector, worn spark plugs or wrong plug gap.
• C1400 — C1400 — Traction Control Valve RF Circuit Failure. A fault in the ABS / stability control. Short, gentle driving to a shop is usually possible. Typical causes: failed wheel speed sensor, blown fuse or low voltage to the ABS module, damaged tone (reluctor) ring on the hub.