Curing the C123EF0 Fault Code

Fault code C123EF0 in Audi and VW vehicles signals an internal failure of the ABS pump, a critical component in your car’s braking system. This issue is often a consequence of a faulty brake booster pressure sensor, which initially triggers the C11EC04 fault code. If the C11EC04 issue is left unaddressed, it can strain the ABS system, eventually leading to ABS pump failure and the appearance of C123EF0

At ECU Fix, we provide a low-cost alternative to expensive ABS pump replacements with our specialized ABS pump repair service. Instead of purchasing a brand-new unit, our expert technicians can repair your existing ABS pump, restoring it to full functionality at a fraction of the cost inclusive of a lifetime repair warranty and nationwide collection within the UK.

Vehicles this type of ABS pump can be found fitted to include:

  • Audi A4 (2015 – 2020) / Audi A5 (2016 – 2020) / Audi A6 / Audi Q7 / Audi Q5 / Audi SQ7 / Audi SQ5 / Audi RS7 / Audi RS5 / Audi S4 / VW Toureg

Part numbers of this type of ABS pump include:

  • 8W0907379J / 8W0907379Q / 8W0907379AF / 8W0614517N / 8W0614517H / 4M0907379K / 4G0907379T / 80A907379E / 8W0907379AA
  • 0265956241 / 0265956658 / 0265956840 / 0265956194 / 0265956226 / 0265956659

How it Works


Select an ECU from our catalogue and complete the checkout

We arrange courier collection of the ECU

We test and repair the ECU within 2-3 working days

The ECU is returned via courier and ready to fit

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