ABS
C123E F0 / C123EF0
Audi ABS: hydraulic brake booster limit reached
The ABS unit reports that the hydraulic brake boost has reached its limit. Simply clearing the fault does not solve this, but we can repair it in a remote session with your car.
- Module
- ABS/ESP control unit
- How we work
- Remotely
- Price
- Individual quote
Symptoms
- The ABS and traction control lamps are on
- A red brake warning lamp or a brake system message appears
- The ABS unit reports C123E F0, also written C123EF0: Hydraulic brake booster limit value reached
- Clearing the fault does not help
Scope of work
- Reading the ABS unit and the full fault log
- Confirming the cause before the repair
- Repairing the fault remotely
- A final check of the brake system
What we need from you
- VIN, model and year
- Full fault log from a diagnostic scan
- Part number of the ABS unit
- Information about earlier brake repairs
- A compatible diagnostic interface
Important
The brake system is critical to safety. If a red brake warning lamp or message appears, follow the message in the car and do not continue driving. Software work does not replace a mechanical repair: if the diagnosis points to a damaged pump or sensor, it must first be repaired or replaced.
Compatible vehicles and versions
Most often reported on the Audi A4, A5, A6, A7, S4, S5, SQ5, Q7 and SQ7, usually from 2015 onwards.
Related services
Tell us what the car needs.
Send the model, year and problem. We will confirm the scope and the price before any work starts.