Several years ago when I replaced the old engine with the new one, I decided
to run an electric fan. I first used a Zirgo, (piece of junk, short lived)
and finally went with a 16" Spal fan. It`s a puller fan.
I used this relay that comes on at 100C.
Auxiliary Fan Switch Part #: 006-545-14-24
I also wired in a MB rocker switch from a W201 or W124. The one that has the red dot and 3 circular arrows.
I thought the red dot was a light, but doesn`t seem to come on.
With my daily running around on a hot day, it never comes on. Seems to be plenty of air flow even in city driving.
How ever let it sit a while idling, it will kick on.
Shut the eng off, and it will run till it brings the temp down.
I also wired in the orange Relay MSFrank posted. There is also a green Relay with a separate fuse.
I have found them in the yards in the trunk of later model MB`s.
I have them wired in under the black box on the drivers side inner fender.
I removed the plug and as much of the wire (in PNP) and wired this in under the box. then it all looks factory.
One is 30 amp and the other 40 amp.
This question has been brought many times in the past.
There has been much gnashing of teeth, wringing of hands and sweaty arm pits condemning the use of anything but what MB installed from the factory.
It is what it is, and wonder how many of these people still actually own one of these cars today?
Charlie