If you take off the black lid to the modules (where it says battery in trunk), there should be about 4 small Delco fuses on top of one of the modules (I think it's the base module). You may want to check those. It's a cheap and easy fix, if it will work.

You may want to pull those modules out and reinsert them while you are there, in case there is a contact issue.

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1993 400E, 256,000 miles (totaled)
1994 E420, 200,000+ miles
1995 E420, 201,000 miles