Coolant Temperature sensor on my 300E
 

Where is it?? I've read extensively about the Cool Harness and am 99% sure a buddy of mine will make the mod for me but after much digging and searching of these forums, I have found nothing to help me locate this booger! :(

Any help will be most appreciated!

Thanks! Mike

On top of the engine, right close to the firewall, with two wires plugged on top of it.

Thanks and another one!
 

Found it and appreciate the response. Talked to my buddy and he suggested simply tapping into the harness (somewhere?) and turn on the aux fan to high speed whenever the A/C is turned on. Reason being, as I sit at a stoplight on a 90-plus degree day (most everyday here in Phoenix :-), the temp of the blown air gradually increases.

In my business, I'm in and out of the car looking at houses with clients and car has no chance to cool down between houses and consequently cabin temp is not so good, which in turn doesn't make for happy clients.

What do any of you think of this idea and how would we go about doing it? By the way, I do admit I'm probably a bit low on Freon but how much does that affect this situation?

Thanks as always for your help! Mike

aux fan
 

Since you probably have the A/C on 99% of the time, being in AZ and in traffic, why not have the fan run HIGH all the time.

Remove the 2-pin connector of the "Engine temp sensor" found a several inches ahead of the "Coolant temp sensor" and jumper it. This will trigger the aux fan relay which will make your aux fan run on HIGH all the time.

Another solution, bypass the RESISTOR, which keeps your aux fan running on LOW once a certain press is achieved within your A/C circuit. It's located right behind the left headlight under the ABS controller thingy. This would probably be better....

good luck,