P2D8BFan 2 Control Module Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- With P2D8B the module that drives fan 2 fails a plausibility or self-test: it has supply and receives a request, yet the status or speed it reports does not fit. Audi's TSB 2081184/1 for the 2025 Q5 family lists P2D8B next to P2D88 and the local LIN bus error U366500, all stored in the thermal management control unit (address 00C5). In those cars earth point 642 of the electrically controlled fan at the front right had been fitted incorrectly; production changed on 28 May 2025, and in service the ground is checked and repaired, with photos for the warranty claim. On other vehicles a worn motor, foreign objects in the blades or water in the connector are more likely. Typical complaints are a lit engine warning lamp and an air conditioning that no longer cools. Fan 1 has P2D88.
- What you may notice
- Engine warning lamp on
- Air conditioning without cooling
- Fault stored intermittently or permanently
- Likely causes
- LikelyDamaged or incorrectly fitted ground point of fan 2
- PossibleForeign objects or worn bearings slowing fan 2
- PossibleInternal electronics fault of the fan 2 module
- RareWater ingress or corrosion at connector or LIN line
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.