Name that wire:
 

The green wire in the photos comes through the body at the passenger's side LH footwell. It travels to the RH rear corner of the transmission on the 1985 380 SE gas body. It appears to be connected at a one pin connector at the RH rear of the transmission. The other part of the connector seems to rest on the lip to which the transmission oil pan fastens. It runs toward the front of the transmission on that lip and turns the front RH corner. It appears to make that turn to the left across the front of that lip. That is where my investigation ends since the wire is broken at that point.

If that wire is on the 1984 300SD body it is not in the same location for the SD body has no wire nor hole in that location.

I can't trace the wire across the center portion of the SE body because it hides inside a huge wiring harness/loom.

It definitely sounds like the wire for the electrical kickdown switch. Power from the kickdown switch behind the accelerator pedal to the electrical kickdown solenoid on the transmission.

https://www.startekinfo.com/StarTek/outside/12253/program/ETM/126td83-85.pdf

Page 109 & 109/1

Also, note the difference between the 84 model vs the 85, which has the Compressor Cut-out Control Unit for the A/C. This may explain the slightly different routing of the wiring.

One of the two kickdown wires runs through connector 146 which is in RH drivers footwell. The other runs straight from the kickdown switch to the kickdown solenoid. I know this because I accidentally jerked the wire out of the kickdown solenoid on the gas body when I removed the engine/transmission assembly. I have replaced it with the one from the diesel body.

That green wire is the oxygen sensor which attaches in that area of the exhaust. I just had to study the FSM electrical diagrams one page at a time until I found a .1mm green wire which matched something that might be found in that location.

I just had to do the FSM ele drawings one page at a time to figure this one out. It wasn't the first wire I couldn't identify. I'm getting pretty good with the symbols and designations on those pages.

Bob. I name that wire Bob - a perfectly respectable name for a wire.

Dan

Bob it is!

BTW, I'm cutting bob off at at the console where he hides then I'm and I'm caulking dat hole with some gue.

Seems sensible to me!

Dan