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.

U3028 — U3028 - Control Module Input Power D Circuit Low (U3028): 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, a faulty module pulling the bus down.
U3029 — U3029 — U3029 - Control Module Input Power D Circuit High. 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.
U3030 — U3030 - Control Module Input Power D Circuit Open (U3030): 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, a faulty module pulling the bus down, corroded connectors, especially in wet areas.
U3031 — U3031 — U3031 - Control Module Input Power D Circuit Intermittent. 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.
U3032 — U3032 — U3032 - Control Module Input Power D Circuit Performance. 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, water ingress in harness junctions.
U3033 — U3033 — U3033 - Control Module Input Power D Circuit Range. 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, a faulty module pulling the bus down, damaged CAN bus wiring or short to power/ground.
U3035 — U3035 - Control Module Ground Circuit Low (U3035): 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, water ingress in harness junctions, aftermarket equipment interfering with the bus.
U3036 — OBD2 code U3036 flags a problem with the vehicle network (CAN bus) communication (U3036 - control module ground circuit high). Short, gentle driving to a shop is usually possible. Common culprits: corroded connectors, especially in wet areas, water ingress in harness junctions, aftermarket equipment interfering with the bus.
U3037 — U3037 - Control Module Ground Circuit Open (U3037): 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, water ingress in harness junctions, a faulty module pulling the bus down.
U3038 — U3038 - Control Module Ground Circuit Intermittent (U3038): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by poor grounds or low battery voltage, corroded connectors, especially in wet areas, a faulty module pulling the bus down.
U3039 — OBD2 code U3039 flags a problem with the vehicle network (CAN bus) communication (U3039 - control module ground circuit performance). 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.
U3040 — OBD2 code U3040 flags a problem with the vehicle network (CAN bus) communication (U3040 - control module ground circuit range). Short, gentle driving to a shop is usually possible. Common culprits: aftermarket equipment interfering with the bus, poor grounds or low battery voltage, water ingress in harness junctions.
U3041 — U3041 - Vehicle Identification Number Not Programmed (U3041): 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, corroded connectors, especially in wet areas, aftermarket equipment interfering with the bus.
U3042 — U3042 - Vehicle Identification Number Mismatch (U3042): 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, a faulty module pulling the bus down, aftermarket equipment interfering with the bus.
U3043 — U3043 - Vehicle Identification Number Invalid (U3043): 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, damaged CAN bus wiring or short to power/ground.
U3044 — U3044 — U3044 - Vehicle Identification Number Not Received. 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, a faulty module pulling the bus down.
U3045 — OBD2 code U3045 flags a problem with the vehicle network (CAN bus) communication (U3045 - vehicle identification number corrupted). Short, gentle driving to a shop is usually possible. Common culprits: water ingress in harness junctions, aftermarket equipment interfering with the bus, corroded connectors, especially in wet areas.
U3046 — U3046 — U3046 - Module Programming Error. 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, aftermarket equipment interfering with the bus, damaged CAN bus wiring or short to power/ground.
U3047 — OBD2 code U3047 flags a problem with the vehicle network (CAN bus) communication (U3047 - module programming incomplete). Short, gentle driving to a shop is usually possible. Common culprits: corroded connectors, especially in wet areas, aftermarket equipment interfering with the bus, a faulty module pulling the bus down.
U3048 — U3048 - Module Programming Failure (U3048): a vehicle fault affecting the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Most often caused by poor grounds or low battery voltage, a faulty module pulling the bus down, aftermarket equipment interfering with the bus.
U3049 — U3049 — U3049 - Module Configuration Error. A fault in the vehicle network (CAN bus) communication. Short, gentle driving to a shop is usually possible. Typical causes: damaged CAN bus wiring or short to power/ground, water ingress in harness junctions, aftermarket equipment interfering with the bus.
U3050 — U3050 - Module Configuration Incomplete (U3050): 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, a faulty module pulling the bus down, corroded connectors, especially in wet areas.
U3051 — U3051 — U3051 - Module Configuration Failure. 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, water ingress in harness junctions, damaged CAN bus wiring or short to power/ground.
U3052 — OBD2 code U3052 flags a problem with the vehicle network (CAN bus) communication (U3052 - module calibration error). Short, gentle driving to a shop is usually possible. Common culprits: poor grounds or low battery voltage, damaged CAN bus wiring or short to power/ground, water ingress in harness junctions.