Originally Posted by wpoll

Sure thing - there's a menu in INPA once you are connected to the DME (DDE in my case) called "Activate" - usually F6 - then you can use the F1 and F2 keys to turn the fan on and off again. It's a little slow to respond, so turn it on, give a second or two to start spinning, then leave it for 15-30 seconds to get up to full speed and stabilise, then turn it off. Al the this is with the ignition on but the engine not running. Watch your battery levels and don't leave the car or fan turned on too long, as this electrical state may deplete your battery in 10-15 mins (or less!).