U0128: Lost communication with the park brake control module
The vehicle network is not receiving messages from the electric parking brake module. The brake may not apply or release with the switch.
| Code | U0128 |
|---|---|
| System | Communication network |
| Group | U01xx, Lost communication with control units |
| Type | Generic: it means the same on every make |
| Can you keep driving? | With care |
What U0128 means
On cars with an electric parking brake, a module drives small motors on the rear callipers when you press the switch. This code means that module has stopped talking to the other control units over the data network. Without it, automatic parking brake and hill start assist may not work.
Most common causes
- Low battery: the motors draw a lot of current and the module drops out when voltage is low
- Blown fuse for the module or brake motors
- Loose, corroded or wet connector on the module or rear callipers
- Damaged wiring, often the harness running to the rear wheels
- Faulty park brake control module
Symptoms
- Parking brake warning light or message on the dashboard
- The parking brake will not apply or release
- Hill start assist not working
- Auto hold disabled
Can you drive with U0128?
With care You can drive if the brake is released, but do not rely on it when parking: leave it in gear or Park and turn the wheels to the kerb on slopes. Get it fixed soon.
Open the bonnetthe in-depth explanation
How to check it
Check battery voltage first: below about 12 V at rest this fault is common. If the brake stays applied, do not drive against it; a garage can release it in service mode with diagnostic equipment.
How to read and clear U0128 with Final OBD
Plug an OBD2 scanner in under the steering wheel, switch the ignition on and open Final OBD. Under Faults you’ll see U0128 with its description and whether it’s confirmed, pending or permanent.
If the engine stores it over standard OBD, with FREE you read this code with its explanation for nothing and clear it. With PRO you also read the faults of every control unit and clear them in all of them.
Clearing the code only turns the light off: if the cause is still there, it comes back. Clear it once it’s fixed, and not right before an inspection. It’s all in how to read and clear fault codes and in inspections and OBD.
Similar codes
- U0124 The lateral acceleration sensor module is not answering on the car network
- U0125 Communication with the multi-axis acceleration sensor module has been lost
- U0126 Lost communication with the steering angle sensor module
- U0127 The tyre pressure monitoring control unit is not answering on the car network
- U0129 The brake system control unit is not answering on the car network
- U012A The chassis control unit A is not answering on the car network
- U012B The chassis control unit B is not answering on the car network
- U012C The active vibration control unit is not answering on the car network
- U0100 Lost communication with engine control module (ECM/PCM A)
- U0101 Lost communication with transmission control module (TCM)
- U0102 Lost communication with transfer case control module
- U0103 Lost communication with the gear shift module
What does code U0128 mean?
On cars with an electric parking brake, a module drives small motors on the rear callipers when you press the switch. This code means that module has stopped talking to the other control units over the data network. Without it, automatic parking brake and hill start assist may not work.
Can you drive with U0128?
You can drive if the brake is released, but do not rely on it when parking: leave it in gear or Park and turn the wheels to the kerb on slopes. Get it fixed soon.
How do you clear U0128?
With an OBD2 scanner and an app like Final OBD, which clears it for free if it’s stored by the engine control unit. But clearing it only turns the light off: if the cause isn’t fixed, U0128 comes back.
Read it on your car
Final OBD reads and clears engine faults through standard OBD for free, each one explained in plain English. With PRO it also reads the faults of every control unit, each make’s own codes included, and clears them in all of them.
