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U003800 — Private CAN bus, no communication

Private CAN bus, no communication. 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 U003800

Porsche Taycan

Porsche 911 (992)

Porsche Panamera (971, 2017–2023)

Porsche Panamera (972, 2024–)

Porsche Cayenne (9YA)

How to read and clear U003800

  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 U003800 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 →

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Other codes of the Roll Control System

C141CF2Motor for motor pump unit, electric machine, overcurrent
C141CF3Motor for motor pump unit, left electric machine, overspeed
C141CF4Motor for motor pump unit, right electric machine, sensor defective
C141CF5Motor for motor pump unit, right electric machine, overspeed
P136C0048V vehicle electrical system, voltage too high
P178E00Compressor for level control, Temperature too high
U006400Infotainment CAN bus faulty
U045200Airbag control unit - signal implausible
U101100Supply voltage – too low
U101200Supply voltage – too high
U10A900Suspension data bus, Faulty
U10EC00Internal CAN, Implausible signal

All 81 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.