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U041800 — Control unit for brake electronics (PSM) – signal implausible
Control unit for brake electronics (PSM) – signal implausible. 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 U041800
How to read and clear U041800
- 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 U041800 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 Brake Booster
| P25C600 | Brake booster temperature sensor - short circuit to ground |
| P25C700 | Brake booster temperature sensor - short circuit to B+ |
| U003700 | Vehicle Communication Bus B |
| U010000 | Engine electronics (DME) control unit – no communication |
| U012900 | Brake electronics (PSM) control unit - no communication |
| U040100 | Engine electronics (DME) control unit – signal implausible |
| U101100 | Supply voltage – too low |
| U101200 | Supply voltage – too high |
| U101400 | Coding |
| U103200 | FlexRay data bus, Initialization failed |
| U104800 | FlexRay data bus, Faulty |
| U110300 | Production mode active |
All 55 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.