Home › Fault codes › U120100
U120100 — Data bus, No communication
Data 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 U120100
Porsche Panamera (971, 2017–2023)
Exterior Sound ActuatorSoundaktuatorAir ConditioningAuxiliary HeaterBCM2 (Body Control Module 2)Mobile Device ChargerSAD2 (Schiebedach2)SAD (Schiebedach)DCDC 48V (Spannungswandler 48V)HDSG (Heckdeckel)WH (Waehlhebel)Light Control LeftLCM_L (Lichtsteuerung links)Light Control RightLCM_R (Lichtsteuerung rechts)Telematics Communication Unit
Porsche Cayenne (9YA)
Exterior Sound ActuatorSoundaktuatorAir ConditioningAuxiliary HeaterBCM2 (Body Control Module 2)Mobile Device ChargerSAD (Schiebedach)DCDC 48V (Spannungswandler 48V)HDSG (Heckdeckel)WH (Waehlhebel)Light Control LeftLCM_L (Lichtsteuerung links)Light Control RightLCM_R (Lichtsteuerung rechts)Telematics Communication UnitWCU – Water Tank Control Unit
How to read and clear U120100
- Plug a standard ENET (Ethernet-to-OBD) cable into your Porsche's OBD port and your Mac or Windows PC.
- Open STEUER14, pick your car and run a fault scan: every control unit is read, and U120100 shows with its status, its full description and the freeze frame when the unit stores one.
- 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 readingOther codes of the Exterior Sound Actuator
| U10D900 | Control unit not installed correctly |
| U110300 | Production mode active |
| U112100 | Data bus - missing message |
| U112200 | Data bus - implausible message |
| U112300 | Data bus – fault value received |
| U120000 | Data bus, Faulty |
| U140000 | Function restriction – supply voltage too low |
| U140100 | Function restriction – supply voltage too high |
| U18C800 | Data bus, Faulty |
| U1A5F00 | Acoustic Simulator (J943), unexpected restart |
All 50 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.