I think they're referring to the control module with the buttons on it in the lower dash section. The small grated areas are where the air gets drawn in to, so there is a fan somewhere in there or accessible from the rear of that unit. I've never heard of that being the issue, but the Germans never cease to surprise me. If you get it out or apart, take some pics and post please.

Pretty easy to get out
https://www.youtube.com/watch?v=nqFB...id=P8C78zswyPQ

ECS has some pics that show all sides of the module. You can see a rather large grate at the back. I assume you can blow it out through there.
http://www.ecstuning.com/BMW-E53-X5-...rols/ES177030/

__________________
Daily Drivers:
- 2008 535i, 320,000km
- 2004 X5 4.4, 01/2004 production, 420,000km
- 1997 328i, 350,000km

Track:
- 1996 328i, track/race car, ~300,000km

Winter:
- 2013 Ski-Doo MXZ X 800 E-TEC, trail can
- 2007 Ski-Doo MXZ Blizzard 800 HO
- 2001 Ski-Doo MXZ 600 w/800 engine, exhaust
- 1978 Ski-Doo Olympique 340 (vintage race sled)
- 1977 Ski-Doo Olympique 340E