The fans on my sisters' 90 civic always stay on, from when you put the car in the on position till you take the key out, it doesnt matter if its 20 below the damn things still run.. It's the stock d15 motor, with AC, both fans run all the time, anyone had this problem before? Which sensors should I be checking and where are they?

 

at least the fan runs, mine doesn't turn on at all, anyways the switch you are looking for is called a thermoswitch which is at the back of the block besides the oil filter. you need to get a new one but before that make sure the wiring going to the switch is not cut somewhere. and its not the fuse cuz it wouldn't run at all if its the fuse. hope this helps

 

RELAYS are stuck. one is located on the left side of the battery on the fenderwall, that one is the cooling fan relay. the other one is located on the right side of the battery(below it), there are TWO, one is the A/c clutch relay and the ac condenser fan relay. Just pull one of the two until the fan turns off, replace both COOLING FAN and AC FAN relays, i sugget a junkyard cause Honda charges like $50 per relay.

If you dont know how the relays look like, they are black and rectangulat shaped and are covered with rubber material.

One of my relays actually got stuck before they stopped working at all.

 

I replaced both relays with wrecker units and the things are still running What does this thermoswitch look like, which side of the oil filter is it on and how many wires are coming out of it?? thnks

 

has this been happening ever since you got the car? I don't think it is really that bad to just let it run like that, but the fan motor is working longer which means it could go out faster. Sounds like someone wired the fan into the underdash fuse box to one of the outlets. Check your fuse box and you will probably see a wire going into it that doesn't look stock. That is how I have my fan hooked up exactly, but I have a switch.