Are you trying to do this in the '95 C280? If not, ignore the rest of this note!
If so, I checked my CD (W140 chassis) and there is a complete schematic for the cell phone. Note that it's an INTERCONNECTION diagram, so the 'boxes' that it connects to are just shown as 'blocks'. But all the wiring is shown and how they all interconnect.
The CD (Popular Mechanics) is good for all cars UP to and including model year 1995. So your car sb in there. FYI!
Regards . . . . JimF
'94 S500 Cpe
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