got the car back just now and it's running fine - it was the #5 fuse that blew.

The fuse cover diagram says something about tachometer - sun roof - a few other things but it is a 25a fuse. the original one was 25 years old - the new ones I bought are deep blue - the old fuse barely had any color in it at all.

__________________
dtf
1994 E320 Wagon (Died @ 308,669 miles)
1995 E300 Diesel (228,000)
1999 E300 Turbodiesel ( died @ 255,000)
2006 Toyota Tundra SR5 AC 4X4 (115,000 miles) rusted frame - sold to chop shop
2011 Audi A4 Avant (165,000 miles) Seized engine - donated to Salvation Army
BMW 330 xi 6 speed manual (175,034 miles)
2014 E350 4Matic Wagon 128,000 miles
2018 Dodge Ram 21,000 miles

This got me to look at the wiring diagrams for W124s and here's what I found:

The pre-92 or 93 W124 diesels have no fuses or relays in the starter circuit.

power goes like this:

unfused battery -> ignition switch -> neutral safety switch (NSS) -> starter solenoid

on a 1995 diesel they added a K38 starter cut-out relay between the ignition switch and the NSS. That relay is controlled by the alarm module.

I didn't trace the wires any further but I think that it is possible that a blown fuse would cause a no-start on a 1995 diesel.


Early cars have a more robust system.

thanks Chris! I am glad the fuses are not like my daughters BMW '06 330ix in the back of the glove box behind a fake wall. what a pain to even look at them.

that K38 might explain what that buzzing noise was coming from the module behind the fuse box too?

__________________
dtf
1994 E320 Wagon (Died @ 308,669 miles)
1995 E300 Diesel (228,000)
1999 E300 Turbodiesel ( died @ 255,000)
2006 Toyota Tundra SR5 AC 4X4 (115,000 miles) rusted frame - sold to chop shop
2011 Audi A4 Avant (165,000 miles) Seized engine - donated to Salvation Army
BMW 330 xi 6 speed manual (175,034 miles)
2014 E350 4Matic Wagon 128,000 miles
2018 Dodge Ram 21,000 miles

I'm not sure what that buzzing might have been.


I can tell you that the K38 is located behind the instrument cluster.