P2D88Fan 1 Control Module Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- How the car detects it
- P2D88 means the electronics of fan 1 do not behave as expected although supply and communication are present: the module reports an internal fault, or the speed it sends back does not fit the request. Audi documents the code for 2025 Q5, Q5 Sportback, SQ5 and SQ5 Sportback in TSB 2081184/1. The thermal management control unit stores P2D88, P2D8B or the LIN error U366500, the engine warning lamp comes on and the air conditioning may stop. The reason was an incorrectly fitted ground of the electric fan at earth point 642 on cars built before 28 May 2025; the workshop inspects and reworks it. A Hyundai patent shows the principle behind such checks: the fan controller returns its measured speed to the engine unit and falls back to fixed duty values when the link fails. Fan 2 has P2D8B.
- What you may notice
- Engine warning lamp on
- Air conditioning stops cooling
- Fan does not run or runs irregularly
- Likely causes
- LikelyPoor or wrongly fitted ground connection of the fan
- PossibleInternal fault of the fan control electronics
- PossibleFan blocked or slowed by debris or bearing wear
- RareMoisture or corrosion in the fan 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.