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U042400 — Air conditioning control unit - signal implausible
Air conditioning control unit - 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 U042400
How to read and clear U042400
- 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 U042400 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 Thermal Management
| U040E00 | Boost pressure actuator for turbocharger 2, no communication |
| U041100 | High-voltage power electronics control unit – signal implausible |
| U041300 | High-voltage battery control unit, signal implausible |
| U041500 | Control unit for brake electronics (PSM) – signal implausible |
| U042200 | Front-end electronics control unit (BCM1) - signal implausible |
| U042300 | Instrument cluster control unit – signal implausible |
| U042500 | Auxiliary heater control unit – signal implausible |
| U042B00 | Control unit for chassis control (PASM) – signal implausible |
| U044700 | Gateway control unit – signal implausible |
| U046400 | Central computer (PCM) control unit – signal implausible |
| U046800 | Fuel cell control unit, implausible signal |
| U046C00 | Electric air-conditioning compressor (V470), – signal implausible |
All 636 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.