U0039
Vehicle Communication Bus B (+) Open
U0039 is an OBD-II diagnostic trouble code meaning: Vehicle Communication Bus B (+) Open. Common causes: bus b wire break (+), poor contact in the connector. Estimated repair cost: $6–56.
Symptoms
- Check Engine Light Is On
- Malfunction of related systems (for example, airbags)
- Lost communication with one or more modules
- Incorrect dashboard readings
Causes
- Bus B wire break (+)
- Poor contact in the connector
- Corrosion or oxidation of contacts
- Malfunction of one of the modules in the network
- Wiring harness damage
How to Fix
- Check the continuity of the Bus B wire (+)
- Inspect and clean the contacts in the connectors
- Check connections between modules
- Scan all modules for errors
- Repair only from an authorized dealer
Related codes
Error U0039 by Vehicle Brand
FAQ
What does the U0039 code mean?
U0039 is an OBD-II diagnostic trouble code that indicates: Vehicle Communication Bus B (+) Open
What causes a U0039 error code?
The most common causes of U0039 include: Bus B wire break (+); Poor contact in the connector; Corrosion or oxidation of contacts; Malfunction of one of the modules in the network.
How do I fix a U0039 diagnostic trouble code?
To fix U0039: Check the continuity of the Bus B wire (+). Inspect and clean the contacts in the connectors. Check connections between modules. For a complete diagnosis, use an OBD-II scanner.
Is it safe to drive with U0039?
Limited driving only, diagnose soon
How much does it cost to fix U0039?
The estimated repair cost for U0039 is $6–56. Actual cost depends on your vehicle, location, and labor rates.
See also: Russian version · NationStat