Fan clutch temp sensor
 

1993 190E, 2.3. Started running hotter than normal, only the aux fan was working. I replaced the mag. fan clutch, still no main fan. I think I have found the temp sensor that controls this fan on the internet but I don't know where it resides on the engine. There are three temp sensor/switch looking suspects on top of the thermostat housing. Is it one of these?

Where exactly is the tempsensor/mag. fan clutch swith on this car?

Thanks a bunch from a new member.

Paul A.

I don't have my book with me any more to look it up for you. But If I were you, I would test the fan clutch by doing this.

Find one of the sensors with two wires on the thermostat housing at the upper radiator hose on the engine side. Start the engine, short out the two wires from the sensor, your fan clutch should kick on. The sensor that controls your fan clutch is nothing but a switch, it completes the circuit to the fan clutch, as temperature rises, the resistance inside the sensor drops, this enable current to go through, and therefore the fan clutch will get its power from.

Alex