Cool harness resistor installed
 

I installed a 1.2k ohms resistor on the 2 prong temp sensor, then I took the car for a drive and as soon as the temp in the 400E got to the 100 degrees the aux fans kicked in. Good little trick keeping it cool in the summer months!!!!:D

Good to know it works. Did you solder it to the connector or the sensor? I'm not sure I trust my limited soldering skills lol.

I soldered it to the connector, took me three tries, cuz I shake like a bastard!!! LOL

But the fans should be kicking in at 100 degrees anyway, shouldn't they?

105C is the factory aux fan kick-on point....

I always thought it was 100... and at 105 the fans start running faster?


Any pics of where to solder?
And, if a k ohm resistor is soldered, would it kick in even earlier?

Also, I know this seems like a good idea... but wouldn't Mercedes know better? I mean, there has to be a reason they didn't do this themselves right?

Mercedes had other priorities to balance out like keeping the engine hot to minimize emissions at the expense of longevity. If their only priority was keeping the engine cool, you wouldn't get so many melted wiring harnesses.

Ok, this seems like a fairly worthwhile mod.

Can you post pictures please of where to put the resistor?
And, would it be better to get the fans to kick in at 95 degrees or so? Considering the thermostat is 87 I believe?

Summer is here, and it will reach around 45 degrees C here

Scroll down on the below link..
I bought the CH-92 about four years ago...works great and looks OEM.
Even at today's price it's worth it..

http://www.k6jrf.com/MB_S500.html

The CH-92 is only available for the older cars?
What about my car, it is a 1994, but has the M111 engine in it (same as the C220 he states to need the Version 2).

RBYCC's link is the one I for the mod all the info is there

I'm sorry 88260e, did you mean that this cool harness is the one you used on your car that you're referring to?
So I cannot simply solder a resistor?

Why solder it when you can slip it over the two prongs.If anything goes wrong the car just reverts to stock.I have been running these for years.
With the resistor in hand, loop both ends of it and slip it over the temp sensor prongs.Then when you connect the plug back on it holds it perfectly in place.
Works great.

Is this using the cool harness or simply a resistor?

olpos, great idea!!! Wish I thought of that! Spetz read above link this mod I think is just for 119 motor V8!!!