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

• B1224 — Fuel Temperature Sensor #1 Circuit Short to Battery (B1224): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by damaged wiring in door jambs or wet areas, blown fuse or failed relay, body control module (BCM) fault.
• B1225 — OBD2 code B1225 flags a problem with the body electrical system (fuel temperature sensor #1 circuit short to ground). The car is usually drivable while you plan the repair. Common culprits: body control module (BCM) fault, corroded or loose connectors, damaged wiring in door jambs or wet areas.
• B1226 — B1226 — Fuel Temperature Sensor #2 Circuit Failure. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: blown fuse or failed relay, damaged wiring in door jambs or wet areas, faulty switch, motor or actuator of the affected system.
• B1227 — Fuel Temperature Sensor #2 Circuit Open (B1227): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by corroded or loose connectors, body control module (BCM) fault, blown fuse or failed relay.
• B1228 — Fuel Temperature Sensor #2 Circuit Short to Battery (B1228): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by corroded or loose connectors, faulty switch, motor or actuator of the affected system, blown fuse or failed relay.
• B1229 — Fuel Temperature Sensor #2 Circuit Short to Ground (B1229): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by body control module (BCM) fault, damaged wiring in door jambs or wet areas, corroded or loose connectors.
• B1230 — OBD2 code B1230 flags a problem with the body electrical system (B1230 — see manufacturer: causes, symptoms & fix). The car is usually drivable while you plan the repair. Common culprits: body control module (BCM) fault, faulty switch, motor or actuator of the affected system, corroded or loose connectors.
• B1231 — OBD2 code B1231 flags a problem with the body electrical system (longitudinal acceleration threshold exceeded). The car is usually drivable while you plan the repair. Common culprits: blown fuse or failed relay, damaged wiring in door jambs or wet areas, faulty switch, motor or actuator of the affected system.
• B1232 — See Manufacturer (B1232): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by corroded or loose connectors, body control module (BCM) fault, damaged wiring in door jambs or wet areas.
• B1233 — Glass Break Sensor Failure (B1233): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by faulty switch, motor or actuator of the affected system, body control module (BCM) fault, damaged wiring in door jambs or wet areas.
• B1234 — OBD2 code B1234 flags a problem with the body electrical system (mirror switch invalid code). The car is usually drivable while you plan the repair. Common culprits: body control module (BCM) fault, corroded or loose connectors, faulty switch, motor or actuator of the affected system.
• B1235 — Window Feedback Failure (B1235): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by blown fuse or failed relay, body control module (BCM) fault, faulty switch, motor or actuator of the affected system.
• B1236 — B1236 — Window Feedback Loss of Signal. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: damaged wiring in door jambs or wet areas, blown fuse or failed relay, corroded or loose connectors.
• B1237 — B1237 — Window Feedback Out of Range. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: faulty switch, motor or actuator of the affected system, blown fuse or failed relay, body control module (BCM) fault.
• B1238 — B1238 — Over Temperature Fault. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: faulty switch, motor or actuator of the affected system, blown fuse or failed relay, body control module (BCM) fault.
• B1239 — B1239 — Air Flow Blend Door Driver Circuit Failure. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: body control module (BCM) fault, corroded or loose connectors, damaged wiring in door jambs or wet areas.
• B1240 — Wiper Washer Rear Pump Relay Circuit Failure (B1240): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by corroded or loose connectors, body control module (BCM) fault, faulty switch, motor or actuator of the affected system.
• B1241 — OBD2 code B1241 flags a problem with the body electrical system (wiper washer rear pump relay circuit short to battery). The car is usually drivable while you plan the repair. Common culprits: faulty switch, motor or actuator of the affected system, body control module (BCM) fault, damaged wiring in door jambs or wet areas.
• B1242 — B1242 — Air Flow Recirculation Door Driver Circuit Failure. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: body control module (BCM) fault, faulty switch, motor or actuator of the affected system, damaged wiring in door jambs or wet areas.
• B1243 — B1243 — Express Window Down Switch Circuit Short to Battery. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: damaged wiring in door jambs or wet areas, blown fuse or failed relay, body control module (BCM) fault.
• B1244 — Wiper Rear Motor Run Relay Circuit Failure (B1244): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by damaged wiring in door jambs or wet areas, body control module (BCM) fault, blown fuse or failed relay.
• B1245 — B1245 — Wiper Rear Motor Run Relay Circuit Short to Battery. A fault in the body electrical system. The car is usually drivable while you plan the repair. Typical causes: corroded or loose connectors, blown fuse or failed relay, body control module (BCM) fault.
• B1246 — Dim Panel Potentiometer Switch Circuit Failure (B1246): a body electrical fault affecting the body electrical system. The car is usually drivable while you plan the repair. Most often caused by faulty switch, motor or actuator of the affected system, blown fuse or failed relay, corroded or loose connectors.
• B1247 — OBD2 code B1247 flags a problem with the body electrical system (panel dim switch circuit open). The car is usually drivable while you plan the repair. Common culprits: faulty switch, motor or actuator of the affected system, corroded or loose connectors, body control module (BCM) fault.