It is possible that there is a bad connection underneath the fuse box, and that current is not reaching the fuse circuitry.
This caused my blower to cease blowing, anyway.
Semibodacious Transmogrifications a Specialty
1990 300D 2.5 Turbo sedan 171K (Rudolf)
1985 300D Turbo TD Wagon 219K (Remuda)
"Time flies like and arrow, yet fruit flies like a banana"