If you searched for a "moter" fuse, that's probably part of your problem. The 126 had the fuse moved externally somewhere ~June 1986, so the very last of the '86es and all '87's have the external fuseholder. I'd expect the W124 to be similar. Look for a plastic "box" somewhere in the wiring bundle near the fuse box. My '86 has the external fuse and has the location in the fusebox card crossed out with magic marker. Mine's after the VIN change, so I can only assume that was a factory "feature".

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Current stable:
1995 E320 157K (Nancy)
1983 500SL 125K (SLoL)

Gone but not forgotten:
1986 300SDL (RIP)
1991 350SD
1991 560SEL
1990 560SEL
1986 500SEL Euro (Rusted to nothing at 47K!)

Gone and wanting to forget:
1985 524TD 167K (TotalDumpster™) [Definitely NOT a Benz]