Error code
OBD2 U0129
OBD2U0129
Diagnostic Trouble Code· Standard OBD-II fault code read from the vehicle's onboard diagnostics.
What it means
Lost Communication With Brake System Control Module.
Severity
highDrive with caution, but it is not recommended to continue driving if the issue seems severe.
Summary
U0129 indicates that there is no communication between the OBD-II system and the brake system control module. This issue affects the data bus related to the brake system.
Symptoms
- Brake system warning light on
- Check engine light on
Common Causes
- Faulty brake system control module
- Data bus connector issues or damage
- Powertrain control module malfunction
Diagnosis
- Use a diagnostic tool like Torque Pro to check for additional codes
- Inspect the brake system control module and its connectors
Fixes
- Replace faulty brake system control module or repair data bus connector issues
FAQ
How can I diagnose U0129?
Use a diagnostic tool to check for additional codes and inspect the brake system control module and its connectors.
Not affiliated with OBD2. Answer summarized from the manufacturer's manual linked above; consult that source for the authoritative procedure.
More OBD2 codes
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- U0101Lost Communication with TCM
- U0102Lost Communication with Transfer Case Control Module
- U0103Lost Communication With Gear Shift Module
- U0104Lost Communication With Cruise Control Module
- U0105Lost Communication With Fuel Injector Control Module
- U0106Lost Communication With Glow Plug Control Module
- U0107Lost Communication With Throttle Actuator Control Module
- U0108Lost Communication With Alternative Fuel Control Module
- U0109Lost Communication With Fuel Pump Control Module
- U0110Lost Communication With Drive Motor Control Module
- U0111Lost Communication With Battery Energy Control Module 'A'