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U016400 — Air conditioner control unit - missing message

Air conditioner control unit - missing message. 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 U016400

Porsche Taycan

GatewayThermal Management

Porsche 911 (992)

Battery Energy Control ModuleEngine Control Module 1GatewayTME (Thermomanagement)

Porsche Panamera (971, 2017–2023)

Battery Energy Control ModuleEngine Control Module 1GatewayTME (Thermomanagement)

Porsche Panamera (972, 2024–)

Battery Energy Control ModuleEngine Control Module 1GatewayTME (Thermomanagement)

Porsche Cayenne (9YA)

Battery Energy Control ModuleEngine Control Module 1GatewayTME (Thermomanagement)Torque Converter (Transmission)

How to read and clear U016400

  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 U016400 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 Gateway

U014100Front-end electronics control unit (BCM1) - no communication
U014600Gateway control unit - no communication
U014A00Lost Communication With Battery Energy Control Module "C"
U014B00Gateway – incorrect signal
U015100Airbag control unit - missing message
U015500Instrument cluster control unit - missing message
U016600Auxiliary heater control unit - no communication
U018300Lost Communication With Lighting Control Module Rear
U019900Driver-side door control unit - no communication
U019B00High-voltage charger (OBC) control unit – missing message
U020000Door control unit, passengerʼs side - no communication
U020700Control unit for front panoramic roof - 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.