Originally Posted by romano

hi all
I have a 93, 190E.
I have a question about the blue sensor please, when connected the aux. fan will start and stays running as long as the engine is running. I have removed the plug of the blue sensor just to get the aux.fan to stop and I didnt think I will ever need that fan anyway. Any ideas on what might be the problem here and if its OK to leave the sensor diconnected?
The location of the sensor I am referring to is described below:

If we start from the firewall to the front of the car:

4 pin sensor = Igniton and injection sensor
2 pin sensor(blue)= aux. fan/ac
3 pin sensor=motor temp gauge and radiator fan

thanks