Which aux fan temp switch should I use?
 

I need to replace my Aux fan temp switch in my 1986 w201 190E 2.3-16v.
The OEM factory switch is a 006 545 6124. It is labeled as a 105degree/120degree switch. How does that work? Does it come on at 105 or at 120?
I am considering using a different switch to make it come on sooner. The 006 545 4224 is a 100/110degree switch and the 006 545 4524 is a 105/115degree switch. Would is make sense to use one of these other switches to get the fan to come on sooner that the oem switch does? I have heard of people doing this to get the often very hot 2.3-16v engine a fan blowing on it sooner.
Any advice?

If you add a resistor (1.1kohm I think) across the prongs, your fans will cut on at 92° I think. Has to be the right resistor though or they may turn on earlier than 92° But if you're running hot you may want to find the actual cause first. If there is no problem and you just want to run the engine cooler I'll post a link to a thread you can check out.

Want the fan on sooner
 

Yes, I don't think I really have any cooling issues and there aren't any over heating problems or failing parts. I just want to see if I can get the fan on sooner to keep the temps down. In traffic the car gets quite hot especially with the a/c running.
Any one sure of the size of the resistor to use across the terminals of the temp probe?

Chris,
You might want to take a look at Jim Forgione's great site on Mercedes. While he has articles on C140 maintenance he also offers a resistor for all models. I used one in my '93 CE320
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