Recently my 1989 Civic LX 1.5L has been overheating in stop and go driving. I noticed that the 2 fans behind the radiator are not working. First, I thought the smaller drivers side fan was supposed to come when the key is turned on and it is supposed to run continuosly. Secondly, the larger passenger side fan is supposed to switch on when the coolant temp. exceeds a certain level.

Here is what I've done so far: Checked the under dash fuse...OK. Checked the thermo switch (on the back side of the engine above the oil filter) by unplugging the switch and closing the circuit with a heavy guage copper wire...large fan does not come on when the key is on or when the engine is running...so I guess the thermo switch is probably OK.

Are there relays associated with these 2 fans? If so, where are they located and how do I test if they are OK? Also, how can I test the fan motors to see if they are OK? Have I missed anything else?

Thanks in advance for your help.

 

No. The smaller fan on the drivers side is for the air conditioning and only comes on when it is on. You are right on the passenger side one. I am not 100% positive, but the relay for the big fan is on the passenger side fenderwell behind the headlight and the air conditioning relays are the ones that are on the metal bracket that bolts to the core support behind the passenger headlight.

 

the relay is right on the fan at the bottom of the connector, ur best way of testing out the fan motor is just hooking it directly up to a 12 volt power source with a spare peice of test wire, i currently have mine just rigged into a 12 volt power source that turns the fan on every time the car is on and off when the car is off. cuz mine wasnt working b4 and it wasnt the fuse, relay or other parts in the circuit so i said screw it and made my own circuit loop.

 

u could just have burnt out motors...my cooling fan wasn't going on for a while and when i would stop or go through a drive through the engine would overheat...try unplugging ur fan and hooking up wires from it to the battery and seeing if the fan then comes on...if it still doesn't then ur fan motor is probably burnt out. and if u have a/c in ur car then the one on the right side i think shoudl only come on when the a/c is on. anyway...try that

 

mine were having the same problem.. i just wired them up to a switch that i mounted on my dash so that i can manually turn on my fans.. you should try that.