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

• C1201 — C1201 — ABS Inlet Valve Coil LF Circuit Short To Ground. A fault in the ignition system. Short, gentle driving to a shop is usually possible. Typical causes: faulty ignition control circuit in the ECM, damaged coil wiring or connector, failed ignition coil or coil pack.
• C1202 — OBD2 code C1202 flags a problem with the ignition system (ABS outlet valve coil rear circuit failure). Short, gentle driving to a shop is usually possible. Common culprits: worn spark plugs or wrong plug gap, failed ignition coil or coil pack, moisture or oil in the spark plug wells.
• C1203 — OBD2 code C1203 flags a problem with the ignition system (ABS outlet valve coil rear circuit open). Short, gentle driving to a shop is usually possible. Common culprits: failed ignition coil or coil pack, faulty ignition control circuit in the ECM, damaged coil wiring or connector.
• C1204 — ABS Outlet Valve Coil Rear Circuit Short To Battery (C1204): a chassis (brakes/steering/suspension) 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, failed ignition coil or coil pack.
• C1205 — ABS Outlet Valve Coil Rear Circuit Short To Ground (C1205): a chassis (brakes/steering/suspension) fault affecting the ignition system. Short, gentle driving to a shop is usually possible. Most often caused by faulty ignition control circuit in the ECM, failed ignition coil or coil pack, worn spark plugs or wrong plug gap.
• C1206 — OBD2 code C1206 flags a problem with the ignition system (ABS inlet valve coil rear circuit failure). Short, gentle driving to a shop is usually possible. Common culprits: faulty ignition control circuit in the ECM, damaged coil wiring or connector, failed ignition coil or coil pack.
• C1207 — OBD2 code C1207 flags a problem with the ignition system (ABS inlet valve coil rear circuit open). Short, gentle driving to a shop is usually possible. Common culprits: damaged coil wiring or connector, failed ignition coil or coil pack, moisture or oil in the spark plug wells.
• C1208 — ABS Inlet Valve Coil Rear Circuit Short To Battery (C1208): a chassis (brakes/steering/suspension) 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, faulty ignition control circuit in the ECM.
• C1209 — ABS Inlet Valve Coil Rear Circuit Short To Ground (C1209): a chassis (brakes/steering/suspension) fault affecting the ignition system. Short, gentle driving to a shop is usually possible. Most often caused by faulty ignition control circuit in the ECM, damaged coil wiring or connector, worn spark plugs or wrong plug gap.
• C1210 — OBD2 code C1210 flags a problem with the ignition system (ABS outlet valve coil RF circuit failure). 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, failed ignition coil or coil pack.
• C1211 — ABS Outlet Valve Coil RF Circuit Open (C1211): a chassis (brakes/steering/suspension) fault affecting the ignition system. Short, gentle driving to a shop is usually possible. Most often caused by moisture or oil in the spark plug wells, failed ignition coil or coil pack, damaged coil wiring or connector.
• C1212 — ABS Outlet Valve Coil RF Circuit Short To Battery (C1212): a chassis (brakes/steering/suspension) fault affecting the ignition system. Short, gentle driving to a shop is usually possible. Most often caused by damaged coil wiring or connector, faulty ignition control circuit in the ECM, failed ignition coil or coil pack.
• C1213 — OBD2 code C1213 flags a problem with the ignition system (ABS outlet valve coil RF circuit short to ground). Short, gentle driving to a shop is usually possible. Common culprits: faulty ignition control circuit in the ECM, failed ignition coil or coil pack, damaged coil wiring or connector.
• C1214 — C1214 — ABS Inlet Valve Coil RF Circuit Failure. A fault in the ignition system. Short, gentle driving to a shop is usually possible. Typical causes: faulty ignition control circuit in the ECM, damaged coil wiring or connector, moisture or oil in the spark plug wells.
• C1215 — C1215 — ABS Inlet Valve Coil RF Circuit Open. A fault in the ignition system. Short, gentle driving to a shop is usually possible. Typical causes: worn spark plugs or wrong plug gap, moisture or oil in the spark plug wells, failed ignition coil or coil pack.
• C1216 — ABS Inlet Valve Coil RF Circuit Short To Battery (C1216): a chassis (brakes/steering/suspension) fault affecting the ignition system. Short, gentle driving to a shop is usually possible. Most often caused by failed ignition coil or coil pack, faulty ignition control circuit in the ECM, moisture or oil in the spark plug wells.
• C1217 — ABS Inlet Valve Coil RF Circuit Short To Ground (C1217): a chassis (brakes/steering/suspension) 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, faulty ignition control circuit in the ECM.
• C1218 — OBD2 code C1218 flags a problem with the ABS / stability control (lamp ABS warning output circuit failure). Short, gentle driving to a shop is usually possible. Common culprits: damaged sensor wiring or corroded connector, blown fuse or low voltage to the ABS module, faulty ABS module or pump motor.
• C1219 — C1219 — Lamp ABS Warning Output Circuit Open. A fault in the ABS / stability control. Short, gentle driving to a shop is usually possible. Typical causes: damaged sensor wiring or corroded connector, failed wheel speed sensor, blown fuse or low voltage to the ABS module.
• C1220 — Lamp ABS Warning Output Circuit Short To Battery (C1220): a chassis (brakes/steering/suspension) fault affecting the ABS / stability control. Short, gentle driving to a shop is usually possible. Most often caused by failed wheel speed sensor, damaged sensor wiring or corroded connector, blown fuse or low voltage to the ABS module.
• C1221 — C1221 — Lamp ABS Warning Output Circuit Short To Ground. A fault in the ABS / stability control. Short, gentle driving to a shop is usually possible. Typical causes: damaged tone (reluctor) ring on the hub, faulty ABS module or pump motor, blown fuse or low voltage to the ABS module.
• C1222 — Speed Wheel Mismatch (C1222): 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, open or shorted wiring in the circuit, faulty sensor or actuator of the affected circuit.
• C1223 — C1223 — Lamp Brake Warning Output Circuit Failure. A fault in the ABS / stability control. Short, gentle driving to a shop is usually possible. Typical causes: blown fuse or low voltage to the ABS module, damaged sensor wiring or corroded connector, failed wheel speed sensor.
• C1224 — C1224 — Lamp Brake Warning Output Circuit Open. A fault in the ABS / stability control. Short, gentle driving to a shop is usually possible. Typical causes: damaged tone (reluctor) ring on the hub, damaged sensor wiring or corroded connector, failed wheel speed sensor.