Lost Communication With Park Brake Control Module
What does U0128 mean?
The U0128 code means the vehicle's onboard diagnostic system has detected: Lost Communication With Park Brake Control Module. This is a critical severity code.
Common Symptoms
- Electronic parking brake warning light on
- Parking brake will not engage or release
- Parking brake stuck in applied position
- Service park brake message on dashboard
- Hill hold assist not functioning
Probable Causes (Ranked by Likelihood)
- Failed electronic park brake control module Very High
- Damaged CAN bus wiring to park brake module High
- Park brake actuator motor failure Moderate
- Low battery voltage preventing module communication Moderate
- Water intrusion in park brake module or actuator Low
Step-by-Step Diagnostic Procedure
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Scan for DTCs in the park brake and chassis modules
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Check battery voltage -- electronic park brakes need adequate voltage to operate
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Inspect CAN bus wiring and connectors at the park brake module
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Verify power supply and ground at the park brake module
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Check park brake actuator motors at each rear wheel for operation
Frequently Asked Questions
Can I drive with code U0128?
If the parking brake is stuck applied, do not drive. If the parking brake is released, you can drive short distances, but you will have no electronic parking brake for parking. Use wheel chocks on inclines.
What causes U0128?
A failed electronic park brake module is the most common cause. Low battery voltage, wiring damage, and actuator motor failures can also trigger this code.
Can I manually release the electronic parking brake?
Many vehicles have a manual release procedure for the electronic parking brake, usually involving a tool or hidden release lever. Check the owner's manual for your specific vehicle.