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U005400 — Extended CAN bus, single-wire operation

Extended CAN bus, single-wire operation. The Taycan, 911 (992), Panamera (971), Panamera (972) and Cayenne 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 U005400

Porsche Taycan

Porsche 911 (992)

Porsche Panamera (971, 2017–2023)

Porsche Panamera (972, 2024–)

Porsche Cayenne (9YA)

How to read and clear U005400

  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 U005400 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 Gateway

U001800Comfort CAN bus, single-wire operation
U002800Hybrid CAN bus – faulty
U002900Hybrid CAN bus - no communication
U003600Vehicle Communication Bus A (-) shorted to Bus A (+)
U004600Vehicle Communication Bus C
U004700Extended CAN bus - no communication
U006400Infotainment CAN bus faulty
U006500Infotainment CAN bus - no communication
U007200Infotainment CAN bus, single-wire operation
U008100Vehicle Communication Bus F Performance
U008A00Vehicle Communication Bus G Performance
U010000Engine electronics (DME) control unit – no communication

All 374 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.