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B177B04 — Servo motor for rear left center horizontal vent – defective
Servo motor for rear left center horizontal vent – defective. The Taycan, 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 B177B04
How to read and clear B177B04
- 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 B177B04 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 Air Conditioning
| B176E04 | Servo motor for front left center horizontal vent – defective |
| B176E09 | Servo motor for front left center horizontal vent – component fault |
| B176F04 | Servo motor for center front left vertical vent – defective |
| B176F09 | Servo motor for front left center vertical vent – component fault |
| B177A04 | Servo motor for center front right vertical vent – defective |
| B177A09 | Servo motor for front right center vertical vent – component fault |
| B177B09 | Servo motor for center rear left horizontal vent – component fault |
| B177C04 | Servo motor for center rear left vertical vent – defective |
| B177C09 | Servo motor for center rear left vertical vent – component fault |
| B177D04 | Servo motor for center rear right vertical vent – defective |
| B177D09 | Servo motor for center rear right vertical vent – component fault |
| B177E01 | Coolant temperature sensor on heat exchanger - electrical fault |
All 418 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.