How to check if my fans work in my 1992 subaru impreza

check fan and resistance

Take the negative battery cable off for one minute.

Here is how to retrieve codes on the Subaru: http://www.2carpros.com/articles/subaru-diagnostic-trouble-code-definitions-1987-1994-obd1-with-code-gathering

check voltage at fans conectors , check relays

The fans are controlled by the ECU, the thermostat and the communication between the two. Most likely scenario is a faulty temp sensor - a switch, that tells the ECU how hot the coolant is - and such a faulty switch will prevent the fans from working correctly. If you turn the A/C on, or switch to defrost, at least one of them should be running all the time. Alos, very important, make sure your coolant level is correct. These sensors only measure temp in liquids, if there is not enough coolant to get a correct flow through the system, the fans will not work properly either.
Hope that helps! Btw: I had the same problem in my 99 Impreza Brighton, turned out to be a faulty temp sensor.

1st, is there a check engine light on? if so have it scanned for trouble codes. Check all fuses & main box fuses under hood. it may also be the temp. fan sensor, you might try the A/C on to see if the fans come on, that will tell you if the fans are ok, which may point to the sensor.

Had a related/similar problem with my 1995 Subaru Impreza; cooling fans would come on and check engine light would illuminate (while fans were running). Problem resolved with replacement of coolant temperature sensor.

change the radiator and the temperature sensor as this controlls when the fans work.
the sensor is normally fitted into one side of the radiator

check the fuse and relay for your coolant fans,and verify your coolant is full in the radiator and reserve

It is in tank. Take out back seat squabs and rear luggage carpet. There should be a removeable panel usually black on the floor. the pump and sender are under this. Change pump for a Walbro 255 LpH but leave the original filter sock. It is better than the Walbro one.

You could have a blown fuse, bad relay, bad blower motor resistor pack, or just a bad blower motor. Start with checking your fuse to make sure you have power to you blower motor.