Hey all. This is my first post here. Here goes...

The electric fan in my '94 940 is not shutting off as soon as it used
to and is draining the battery. I should point out that It does shut
off eventually, it just takes a while. The car is equipped with a bosch
ignition system. To my knowledge, the ECU uses a temp signal from the
ECT to control when the fan turns on/off. I've recently replaced the
ECT so I've ruled that out. This leaves the culprit to be a sticking
cooling fan relay, found behind the battery. It looks like this:



Is there a way to test this relay to determine if its sticking? I dont
really understand how this relay works, and any help would be really
really appreciated!!!

Thanks again!
Roland

p.s. I've already tried looking for a thermo sensor in the radiator
which might control the fan, and I dont believe my system uses one.

 

I always have a tester relay to use but try looking at the wiring diagram in the link and see if it helps.
http://www.volvotechinfo.com/WD123/

 

My car had a problem that when i turned it off the front fan cotinued to run, but it got fixed by itself

 

Hi! I have the same problem on my 1996 940. I already changed the ECT Sensor and the relay, an the fan is still working ALL THE TIME. I have been searching for the Thermoswitch too but didn't find it.

You solved the problem?

 

the thermoswitches that control the fan are on the radiator manifold at the bottom of the radiator. in many configurations, the A/C also turns on the fan.