If it is like my w126 1984 380SE, then take out the glove box and you will see a plug to your left and behind and down from the rear of the bolster(the plastic part) and disconnect the fan. the fuse is used for other things besides the fan.
If you do not want to buy a replacement fan, then disassemble the old one and have the commutator recut and peplace the brushes. mine was so far gone that the commutator looked like the grand canyon and was at least 1/16" DEEPER than where the commutator comes out of the armature. I lucked out with an after market fan and it bolted right up.
You do have to take out the bolster, the plastic foot well cover to get to the fan...on a 126.
Hope this helps.

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1986 Euro 500SEC "RUF" 9:1CR, "Rose"
1985 Euro 500SEC Cabriolet AMG Widebody
1982 Euro 500SEL "Blue"
2001 Texas Heeler (Aussie/Queensland X) "Sulphie",
2012 Queensland Red Heeler "Squeak"
Best dogs I've ever had.