U0128
Lost Communication with Brake Boost Control Module
2006-2011 BMW 325i 3.0L I6 N52 🇷🇺
Critical SeverityNetwork
Description
Cannot communicate with the power brake booster control module on vehicles with electric brake boost.
Symptoms
- Brake pedal feels hard
- Brake boost warning light
- Increased stopping distance
- Brake assist not available
Common Causes
- Electric brake booster module failure
- CAN bus wiring
- Module power loss
- Fuse blown
- Brake booster motor failure
Diagnostic Steps
- Check brake booster module fuse
- Test module power and ground
- Check CAN wiring
- Test brake booster motor
- Check brake fluid level
Repair Notes
Safety critical. Brakes still function but with no power assist. Check fuses and power supply.
Related Codes
Other Network Codes
- U0001High Speed CAN Communication Bus
- U0002High Speed CAN Communication Bus Performance
- U0003High Speed CAN Communication Bus (+) Open
- U0004High Speed CAN Communication Bus (+) Low
- U0005High Speed CAN Communication Bus (+) High
- U0006High Speed CAN Communication Bus (-) Open
- U0007High Speed CAN Communication Bus (-) Low
- U0008High Speed CAN Communication Bus (-) High
- U0009High Speed CAN Communication Bus Shorted Together
- U0010Medium Speed CAN Communication Bus
U0128 on Other Vehicles
Common Questions
What does code U0128 mean on a 2006-2011 BMW 325i?
U0128 stands for "Lost Communication with Brake Boost Control Module". Cannot communicate with the power brake booster control module on vehicles with electric brake boost.
What are the symptoms of U0128 on a BMW 325i?
Common symptoms of U0128 include: Brake pedal feels hard, Brake boost warning light, Increased stopping distance, Brake assist not available.
What causes U0128 on a 2006-2011 BMW 325i?
Common causes of U0128 include: Electric brake booster module failure, CAN bus wiring, Module power loss, Fuse blown, Brake booster motor failure.