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U123400 — MAC address conflict

MAC address conflict. The Taycan report this code; below is which control unit sets it on each model and how to read and clear it.

Which models and control units set U123400

Porsche Taycan

Head-Up Display

How to read and clear U123400

  1. Plug a standard ENET (Ethernet-to-OBD) cable into your Porsche's OBD port and your Mac or Windows PC.
  2. Open STEUER14, pick your car and run a fault scan: every control unit is read, and U123400 shows with its status, its full description and the freeze frame when the unit stores one.
  3. Fix the cause first, then clear the fault memory and scan again to check it stays away. Reading and clearing fault codes is free on every control unit.

More about fault memory in the manual →

Download STEUER14 — free fault reading

Other codes of the Head-Up Display

U111000Function restriction due to missing message
U111100Operating and display log - missing message
U112100Data bus - missing message
U11BB00Ethernet databus branch 1, Electrical error
U120000Data bus, Faulty
U122C00Ethernet databus branch 1, No communication

All 22 codes of this control unit →

Fault names come from the manufacturer's diagnostic data. STEUER14 is independent and not affiliated with Porsche AG. A code tells you what a control unit detected, not always which part failed — check wiring, supply voltage and related codes before replacing parts. STEUER14 shows each fault's full description, status and freeze frame on the car.