It's behind the "Plastico" cover behind the Battery(The EDS ,and OVP relay also
live there...Great place for electronics[At least the fuse box is semi-watertight])

BC is correct it's a complicated little journey for the Electrons to successfully
complete so that you might enjoy "Angel's Breath".

The schematic is from the '90-'91 model ,but yours is similar.

Attached Thumbnails

     

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'84 300SD sold
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