Audi A4 Brake Boost Fault Code C123EF0 Repair London | Specialist Diagnostics
Call 24/7: 07779 836677 / 07448 457247
⚠️ Brake Warning: C123EF0 indicates a brake boost or ABS system fault. Ignoring this can compromise braking performance and vehicle safety.

What Is C123EF0?

C123EF0 is a fault code for the Audi A4 indicating a brake boost / ABS module issue. It can affect brake assistance, ABS, traction control, or high-voltage braking in hybrid models.

Common Causes

  • Faulty ABS / brake boost module
  • High-voltage brake booster errors in hybrid/e-tron models
  • Wiring harness damage or corroded connectors
  • Low brake fluid or hydraulic leaks
  • Communication errors with ECU / TCU

Symptoms

  • Red brake warning light illuminated
  • Limp mode on braking system
  • Pulsation or reduced braking power
  • Error code C123EF0 on diagnostics
  • ABS / ESP warning lights

Our Repair Solutions

We specialise in Audi A4 C123EF0 fault diagnostics and repair across London. Our service includes ABS / brake boost module reconditioning, wiring checks, hydraulic system inspection, and full system testing to restore safe operation.

Questions About C123EF0?

Our specialists are ready to assist — don’t hesitate to get in touch.

📞 Call 07779 836677

Book Audi A4 Brake Boost Repair

Audi A4 C123EF0 Brake Boost Fault Repair London | ABS & HV Brake Specialist