U04B5 – BMW DTC

BMW DTC U04B5 – Invalid Data Received from Brake System Control Module ‘B’

DTC U04B5 meaning on BMW

The DTC U04B5 on a BMW indicates that the vehicle’s onboard diagnostic system has detected invalid data being received from the Brake System Control Module ‘B’. This means that there is a communication issue between the control module and the vehicle’s main computer.

BMW DTC U04B5 symptoms

Symptoms of the DTC U04B5 on a BMW may include:

  • ABS warning light illuminated on the dashboard
  • Brake system malfunction warning message
  • Loss of ABS functionality

BMW DTC U04B5 causes

The common causes of the DTC U04B5 on a BMW are:

  • Faulty wiring or connectors between the control module and the main computer
  • Defective Brake System Control Module ‘B’
  • Software issues within the control module

BMW DTC U04B5 seriousness

The DTC U04B5 should be addressed promptly as it can affect the proper functioning of the vehicle’s braking system, particularly the ABS. Driving with this fault unresolved may compromise the safety and performance of the vehicle.

How to diagnose DTC U04B5 on BMW

To diagnose the DTC U04B5 on a BMW, follow these steps:

  1. Use a diagnostic scanner to retrieve the fault codes stored in the vehicle’s system
  2. Inspect the wiring and connectors between the control module and the main computer for any damage or corrosion
  3. Perform a communication test between the control module and the main computer
  4. If necessary, test the Brake System Control Module ‘B’ for proper functionality

How to fix DTC U04B5 on BMW

To fix the DTC U04B5 on a BMW, you can:

  1. Repair or replace any damaged wiring or connectors
  2. Replace the faulty Brake System Control Module ‘B’
  3. Update the software in the control module if needed

How to erase DTC U04B5 on BMW

To erase the DTC U04B5 on a BMW, you can:

  1. Use a diagnostic scanner to clear the fault codes from the vehicle’s system
  2. After fixing the underlying issue, perform a test drive to ensure the fault does not reoccur

Recommended tools & DTC Scanners for BMW

Best Diagnostic App for modern BMWs: BimmerLink

Recommended Bluetooth adapter for Bimmerlink: OBDLink CX

Cable adapter for Bimmerlink: Enet Cable USB Type C

For older BMWs we recommend: Autel AutoLink AL319 (2024 version)

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

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