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

• U0367 — U0367 — U0367 - Software Incompatibility With Active Safety Control Module 17. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: water ingress in harness junctions, damaged CAN bus wiring or short to power/ground, a faulty module pulling the bus down.
• U0368 — OBD2 code U0368 flags a problem with the vehicle network (CAN bus) communication (U0368 - software incompatibility with active safety control module 18). Short, gentle driving to a shop is usually possible. Common culprits: a faulty module pulling the bus down, damaged CAN bus wiring or short to power/ground, aftermarket equipment interfering with the bus.
• U0369 — U0369 - Software Incompatibility With Active Safety Control Module 19 (U0369): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by water ingress in harness junctions, corroded connectors, especially in wet areas, poor grounds or low battery voltage.
• U0370 — OBD2 code U0370 flags a problem with the vehicle network (CAN bus) communication (U0370 - software incompatibility with active safety control module 20). Short, gentle driving to a shop is usually possible. Common culprits: corroded connectors, especially in wet areas, damaged CAN bus wiring or short to power/ground, poor grounds or low battery voltage.
• U0371 — U0371 - Software Incompatibility With Active Safety Control Module 21 (U0371): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by corroded connectors, especially in wet areas, aftermarket equipment interfering with the bus, poor grounds or low battery voltage.
• U0372 — OBD2 code U0372 flags a problem with the vehicle network (CAN bus) communication (U0372 - software incompatibility with active safety control module 22). Short, gentle driving to a shop is usually possible. Common culprits: water ingress in harness junctions, a faulty module pulling the bus down, corroded connectors, especially in wet areas.
• U0373 — U0373 - Software Incompatibility With Active Safety Control Module 23 (U0373): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by damaged CAN bus wiring or short to power/ground, corroded connectors, especially in wet areas, a faulty module pulling the bus down.
• U0374 — U0374 — U0374 - Software Incompatibility With Active Safety Control Module 24. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: corroded connectors, especially in wet areas, poor grounds or low battery voltage, water ingress in harness junctions.
• U0375 — OBD2 code U0375 flags a problem with the vehicle network (CAN bus) communication (U0375 - software incompatibility with active safety control module 25). Short, gentle driving to a shop is usually possible. Common culprits: poor grounds or low battery voltage, a faulty module pulling the bus down, damaged CAN bus wiring or short to power/ground.
• U0376 — OBD2 code U0376 flags a problem with the vehicle network (CAN bus) communication (U0376 - software incompatibility with active safety control module 26). Short, gentle driving to a shop is usually possible. Common culprits: damaged CAN bus wiring or short to power/ground, aftermarket equipment interfering with the bus, a faulty module pulling the bus down.
• U0377 — U0377 — U0377 - Software Incompatibility With Active Safety Control Module 27. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: aftermarket equipment interfering with the bus, water ingress in harness junctions, a faulty module pulling the bus down.
• U0378 — U0378 — U0378 - Software Incompatibility With Active Safety Control Module 28. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: poor grounds or low battery voltage, water ingress in harness junctions, a faulty module pulling the bus down.
• U0379 — OBD2 code U0379 flags a problem with the vehicle network (CAN bus) communication (U0379 - software incompatibility with active safety control module 29). Short, gentle driving to a shop is usually possible. Common culprits: damaged CAN bus wiring or short to power/ground, aftermarket equipment interfering with the bus, corroded connectors, especially in wet areas.
• U0380 — U0380 - Software Incompatibility With Active Safety Control Module 30 (U0380): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by damaged CAN bus wiring or short to power/ground, poor grounds or low battery voltage, a faulty module pulling the bus down.
• U0381 — U0381 — U0381 - Software Incompatibility With Active Safety Control Module 31. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: poor grounds or low battery voltage, water ingress in harness junctions, corroded connectors, especially in wet areas.
• U0382 — U0382 - Software Incompatibility With Active Safety Control Module 32 (U0382): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by a faulty module pulling the bus down, poor grounds or low battery voltage, aftermarket equipment interfering with the bus.
• U0383 — OBD2 code U0383 flags a problem with the vehicle network (CAN bus) communication (U0383 - software incompatibility with active safety control module 33). Short, gentle driving to a shop is usually possible. Common culprits: corroded connectors, especially in wet areas, poor grounds or low battery voltage, aftermarket equipment interfering with the bus.
• U0384 — U0384 — U0384 - Software Incompatibility With Active Safety Control Module 34. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: poor grounds or low battery voltage, aftermarket equipment interfering with the bus, damaged CAN bus wiring or short to power/ground.
• U0385 — U0385 - Software Incompatibility With Active Safety Control Module 35 (U0385): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by aftermarket equipment interfering with the bus, poor grounds or low battery voltage, damaged CAN bus wiring or short to power/ground.
• U0386 — U0386 — U0386 - Software Incompatibility With Active Safety Control Module 36. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: corroded connectors, especially in wet areas, a faulty module pulling the bus down, aftermarket equipment interfering with the bus.
• U0387 — U0387 - Software Incompatibility With Active Safety Control Module 37 (U0387): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by a faulty module pulling the bus down, water ingress in harness junctions, poor grounds or low battery voltage.
• U0388 — U0388 — U0388 - Software Incompatibility With Active Safety Control Module 38. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: water ingress in harness junctions, damaged CAN bus wiring or short to power/ground, a faulty module pulling the bus down.
• U0389 — OBD2 code U0389 flags a problem with the vehicle network (CAN bus) communication (U0389 - software incompatibility with active safety control module 39). Short, gentle driving to a shop is usually possible. Common culprits: aftermarket equipment interfering with the bus, damaged CAN bus wiring or short to power/ground, corroded connectors, especially in wet areas.
• U0402 — Invalid Data Received From Transmission Control Module (U0402): a vehicle network fault affecting the automatic transmission control. Short, gentle driving to a shop is usually possible. Most often caused by faulty transmission speed sensor, wiring or connector faults in the valve body harness, internal mechanical wear (clutches, torque converter).