edcpus

Maybe someone can help. I have a 98 honda accord lx 4 cyl. the problem i am having is the cooling fans will not kick on, i have replaced two temperature sensors, and fans will not kick on, If i turn on the a/c the fans will work. Once i turn it off they won't work. I change the antifreeze and the lower radiator hose a couple days ago, however the fans were working before then. The fans are brand new, i have check all fuses and relays. Can someone please help me

hondadude

How long did you let the car sit at idle? did the temp guage go above 1/2 way?
I'd like to have a little more info before I go looking up and uploading schematics; What's the rest of the story??

edcpus

ok im in alabama, so it ran for almost and hour before the temp guage went a couple inches to hot, but i shut the car off. However if im driving. the temp will rise up when im stop in traffic, but its sitting in my driveway and it will run hot, the radiator is still full, except after it starts to get hot before overheating the coolant resovior starts to boil.

hondadude

the switch that tells the fans to turn on is the one on top of the T-stat housing, you could try unplugging it and jumper the pins in the plug, then turn on the key and see if the fans run or if you hear any clicking noises from the relay;If there is a ground connector at the T-stat housing be sure it is hooked up and clean. I'll hang with ya here for awhile

edcpus

what do you mean by jumper the pins in the plug

hondadude

put a wire between the 2 terminals, you are faking a signal that the car is so hot the switch is closed

edcpus

that didn't work i have voltage on the plug itself though

hondadude

Do you have a meter? the other pin that doesn't have battery voltage should have continuity to ground. When you jumpered it did you hear the relay in the under hood fuse box 'click?

hondadude

Did you burp the block thru the 12mm bleed screw at the t-stat housing after adding coolant the other day?

edcpus

no i didn't hear the click

hondadude

Next thing to do is pull the relay from the underhood fuse box and jumper a cross the 2 slots that are lined up with the 'long side' of the relay this is jumpering the relay

hondadude

Voltage on one of the 'coil pins' when the fan switch is jumped, jumper across the contact pins to act as a 'closed' relay

fixitman

hey honda man this is edcpus is it anyway i can im you? ive tried all of the relays

Honda-Master

when engine is warmed up is the lower radiator hose almost as hot as the top hose,,,,,,if it is cool or warm you got a t-stat stuck close ,,and if that,s the case the fans will not come on ,,,,,,,,if the fans work with a/c on, it is not the fuses or the relays ,,,and you said you jumped the switch at thermostat housing and still did not work correct ??

fixitman

thats correct

fixitman

i know my access here is limited, but the lower radiator hose is cold after the car warms up, then the thermostat is not working, but how is it that it would cause the fans not to come on, are is there another idea

hondadude

You say the fans were working before you changed the lower hose?? Go back and see what you unplugged while doing that job....I'm looking for a full schematic to upload for you


Modified by hondadude at 7:47 PM 12/31/2005

hondadude

here's the BIG picture for your problem
http://members.troublecodes.ne...s.jpg

fixitman

ok i got diagram now what is actually wrong, i have replace the temperature switch, sensor, of course we know the relays are good. is it possible that the new sensor could be bad as well?

BLKFLSH

Did you burp the system? like hondadude said.

hondadude

Looking at the schematic...if you ground the green wire at the switch plug[key on] the relay should turn on and the fans run, I'm again asking that you review your prior work carefully to see if there is some thing that came unhooked while you were wrestling around with the radiator hose.

Honda-Master

if he said fans work with a/c on ,, it makes me assume that he connected everything properly around the fans .......i still say that if the lower radiator hose is cold when engine is hot , it has a stuck t-stat

hondadude

Thanks for jumping in on this one H-M.. earlier this evening I asked him to try jumpering the plug at the switch and he said the fans still did not run? I know that there must be some other problem??

accordisslow

replace your ETC Switch i had the same problem.

fixitman

what is the etc switch and where is it located