Hoping to catch MB Doc or one of the ultratechs -

What is the path of the big (+) battery cable from the trunk to the engine bay in a W140? Does it run inside or under the cabin? What are the distribution points?

Thanks,
Sixto
93 300SD

I can only tell you where it is on my 92 500 SEL.
There are two cables one a 70mm and the other 10mm. They originate on a terminal block on the wheel well in the trunk where the positive battery cable is terminated, and come up and over the wheel well into the passenger compartment where they run along the sill to another terminal block under the front carpet near the passenger side transmission hump. There is a large capacitor for electrical interference hooked into this block on the 70mm cable. The larger feeds the starter I assume by going thru the floor board or firewall, the smaller supplies voltage to the fuse boxes

Thanks for the info! I think we're getting somewhere. I disconnected the big cable in the passenger footwell. The draw only occurs between the battery and the feed line to the trunk panel when fuse 5, 6, 11, 15 or 16 is fitted. 5 and 6 are for power windows, 11 is for the convenience module, 15 is for ATA(?), IRCL(?) and rear headrests, and 16 is for the stereo. Now to find what they have in common...

Sixto
93 300SD