LiL JoN

i got 99 civic ex cooling fan stopped working and over heats replaced the temp sensor on the thermo housing and the fan relay and nothing tested the fan and works what could it be???? help please

lhd dc2

Have you tried replacing the cooling fan relay to see if the old one is defective and fuse in the engine bay fuse box?

slowhatchcali

put straight power to the fan and see if it turns on..

raidacaipo

check the fuse. I bet its popped. First try a test and take off your fan sensor plug. Then use a paper clip and connect it into the fan sensor plug on both ends. Then turn the key of your ignition on the On position. Your fan should start spinning. If it doesnt then your fuse may have blown out. Check all your fuses underneath your steering wheel. and replace if it popped

lhd dc2

He already stated on the OP that he tested the fan.

slowhatchcali

my bad. sorry

well just do what raidacaipo said and see where it goes from there

raidacaipo

ooops.. I would replace the thermostat then. Sounds like its not opening up??? take it off and put it in a boiling pan. Turn on the stove and wait for it to boil. You should start seeing it slowly opening up. If it doesnt open up, then I would replace it.

http://www.youtube.com/watch?v=dWre_PgeFVY

lhd dc2

Now that I read the OP again. Have you tried replacing the Thermostat itself?

LiL JoN

changed the sensor tried a working fan relay checked all fuses and nothing

LiL JoN

help havent tried the thermostat... but will that make the fan not turn on?????

raidacaipo

just do it then come back to us when it turns on.. :O

Jimster480

the fan wont turn if the thermostat isnt opening. You should just jump the fan to have it run all the time. It runs better that way anyway.

LiL JoN

anyone else so i wont turn if it is stuck open????

EJ2-Fluffy

iTrader: (1)

Check the temp sensor located near the thermostat or near the hoses that controls the fan (which wiring goes to the underhood fusebox)

LiL JoN

ive replaced the sensor already

CarbonizedDX

There are two sensors, the thermo switch sensor(12) on the thermo housings and a temp sensor(13) on the motor just below the top rad hose outlet off the motor. My buddies 99 EJ6 was having issues where the fan wouldn't come on till 3/4-HOT, swapped out both temp, fan temp sensors and the rad cap and it works just like normal now.

I'd also suggest looking at replacing #11 as it's listed as "Thermo Unit", it's a single lead sensor which is probably a grounding switch and it might have an effect as well...

Jimster480

it has no effect. its only for the temp gauge. Then there is another one for the ECU I believe.

CarbonizedDX

Till the OP says otherwise, I'm goin to stick with it will work since I just swapped 12 and 13 and it fixed the high temp reading and no fan...

Jimster480

u can check the wiring for yourself. The fan switch is the sensor at the thermostat, there is no other switch. The fan has no sensors, only that temp switch behind the thermostat.

LiL JoN

help what could it be

raidacaipo

did you do those thermostat test i told you to do? is really easy to remove it and then put it in hot boiling water.. you will see it open up if its working. Do the test and tell us how it goes.. Im like 100% sure its the thermostat not opening..

check list:
*All fuses underneath the steering wheel and replace if necessary
*Replaced fan sensor
*Did fan sensor spinning test
*Hot wire the fan directly to the battery.
*Replace the whole fan unit if the hot wire to the battery test doesnt work.
*Test out thermostat by boiling in hot water on a stove.
*Replace thermostat if it isnt working

LiL JoN

gonna try the thermostat thing but dont think the fan wont work if the thernostat is stuck open ???? should still work

raidacaipo

OMG.... Do you want help or not?

See... you already have 2 members including myself that believe its the thermostat not opening.. you replaced everything else that is more expensive but havent even tried the easiest thing to do without having to spend a penny yet. I suggest you just do it first instead of doubting the advice I have given you because I mentioned several times for you to do this but you still havent.

raidacaipo

this is because you swapped out 12, which is common.. 13 had nothing to do with it..

santacruzccs

the thermostat is the reason why the fan turns on..