Date registered: Dec 2005
Vehicle: 222.132 & 221.122 & 212.025 & 906.633
Mentioned: 3 Post(s)
Quoted: 32 Post(s)
This was asked just a few days ago, I thought it was you, perhaps another one again.
It must be the heater blower regulator that fails and goes to short circuit mode. The blower runs the battery flat soon, take the battery ground wire off if you don't find another way to stop it and need to leave the car unattended for a while.
The AC control unit fuse would not make a difference in this case.