Bosch ESP9 ABS unit repair - C123EF0 - Hydraulic Brake Booster - Limit value reached

Audi ABS Repair – C123EF0 Fault Code: Hydraulic Brake Booster – Limit Value Reached

This is a professional repair service for Audi ABS control modules suffering from the C123EF0 fault – Hydraulic Brake Booster - Limit Value Reached. This issue is typically found in Audi vehicles built between 2010 and 2020, including:

Audi A4, A5, A6, A7, S4, S5, Q5, Q7

Common Part Numbers Affected:

• 8R0 614 517 T

• 8R0 614 517 R

• 8K0 907 379 AD

• 8K0 907 379 AE

• 4G0 614 517 T

• 4G0 907 379 A

Other variants and supersessions of these part numbers may also be covered — contact us if you’re unsure.

Common Symptoms:

• ABS warning light illuminated

• Traction control light on

• “Brake system fault – stop carefully” displayed

• Degraded braking performance

• Emergency braking functions may be reduced or disabled

Important Note: This fault is often caused by a vacuum issue in the vehicle. The fault code will not clear until both the mechanical issue is resolved and the ABS module is properly reset or repaired.

What We Do:

At Get Electronic, we perform a complete teardown and component-level repair of your ABS unit, including:

• Bench testing of communication and fault logging

• Targeted circuit board repairs

• Cleaning and resealing

• Final full-function bench test with test report

We can remove the C123EF0 fault code from the ABS module once the vehicle’s vacuum issue is corrected. The repaired module will then accept a clear scan and function as intended.