BMW Repair: 1990 BMW fuse repeatedly blows!, fuse blows, fuse box

Question
I own a 1990 BMW 325 i, and the fuse, (#10) has repeatedly blown.  In the owners manual, it says that its for the instruments, back up light, and (info center?).  But at the same time, the heater blower doesn't work when its blown.  I have checked the main grounds, but was wondering if there are more that I ought to check, or what could be the possible problem?

Answer
Dear Jeffrey,
Fuse 10 switches on K7 Unloader Relay which in turn switches Fuse 20 that powers the blower fan. This relay is the 3rd from the left at the bottom of the fuse box near fuses 24, 25 and 26. So when fuse 10 blows you have no power to the blower.
Why the fuse blows is another matter. It can be any short in the various circuits powered by Fuse 10. This means any wire in the systems mentioned, or the unloader relay itself, the backup light, the instrument cluster, the seatbelt timer, the transmission range switch, or the check control.
You have to do a point by point detaching of the items mentioned and check if the fuse will not blow when something is not connected. Something like removing the bulbs of the backup light, turning on the key and putting it on reverse, then checking if the fuse will blow. If it still does, then the backup light is not the problem. Do the same on the others mentioned until the fuse no longer blows which means you have isolated the problem.
Tino