I have been noticing my radiator fans will start going at the weirdest times... when the car isn't or hasn't been running for quite some time so the engine temp is well below the temp where the fans would kick on and I am not sure what this could be. Could it be a bad thermostat or are there any other causes to this on hondas?

 

is the key in the 'on' position but the car is not running? if so your AC might be on which is why the fan kicks on. if the key isnt in the car at all i have no idea

 

Yea no key even in the ignition.... I noticed the temp sensor needle in the dash cluster never gets to the middle where I would assume normal operating tempature is so I am thinking the thermostat is stuck open and possibly the water temp sensor is bad which I believe sends the signal to the fans to turn on at certain temps. Still new to hondas so I don't know if this is right but on my nissan that is how it works. Anyone have any input please post up.

 

The first issue is why the fan is getting any power at all with the ignition switched off. :eh: I've never had a fan switch fail on me, so I don't know if they ground out as a fail-safe mode. h:

 

what year is the year and model of your car?

 

'90 Rs

 

have you check the wiring around the cooling fans? i had a 88 prelude si and its fans would kick in after the car was off. that was only after driving. it was some kind of "sport cooling" as the owners manual put it. i don't know if the integra had the same feature.

 

same thing happened to me after i changed the coolant. that fans seem to take longer to come on than before. reflushed, new thermo, new switch, bled air...works a better but not the same.

 

If it makes a difference there is only 1 fan kicking on now that I payed more attention.. I think it is the AC related fan because it is on the drivers side and the smaller of the two. Anyone know what that might mean?

 

jump the switch harness to see if the rad fan still works. if it doesnt turn on then the motor is dead.