9.3.S.I.L.U.D.E.

hello guys might be a noob question but am having trouble figuring out whats wrong with my car the radiator fans will not go on. i checked the fan and its good i also checked all the fuses and the fan relay and their all good. i jumped the cooling fan switch and it still dont go on? does any one have any feedbacks? thanks

black97civic

What vehicle? Factory engine? You cooling fan switch acts as a ground for the fan relay. When the switch closes it turns on the relay which send power to the fan. Best way to diagnose is with a volt meter. Start by checking voltage on both sides of the relay. If they both checkout then check at the power side of the switch. Check the grounds for both the fan switch and the fan. I couldn't tell ya exactly where they are. You can jump the switch by grounding the power wire. That would tell you there a prob with the switch or your ground if the fan turns on.

black97civic

I think the ground for the switch is on the thermostat housing. Maybe someone can verify that.

9.3.S.I.L.U.D.E.

sorry its a 1995 honda civic si d16z6 and thanks black97civic ama go borrow a volt meter and ama check that out

jdp2907

I have an 02 civic ex with the same problem...after it overheated the dealership told me they have to replace two ECT sensors

axis11

Unhook 2-pin connector of radiator fan.
Put a jumper wire on thermo-switch( plugged at thermostat housing).
Switch to ON II.
Use a test light or voltmeter to see if there is battery voltage on the 2-pin connector of radiator(wire side).One wire should have voltage.
Test for continuity of the other terminal to body ground. You should have continuity.

If no voltage at 2-pin connector:
Remove fan relay(underhood fuse/ relaybox)
Key still on ON II, thermo-switch jumped
Use your voltmeter or test light, check for voltage on each of the 4 pin slots of the relay.
You should have 2 points energized. If you get none or only one,
Check The ff. fuse
# 41(80A)
# 42(40A)
# 57 (20A)
All the above are in the under hood fuse/relay box.
#17 (7.5A) Underdash fuse relaybox.

9.3.S.I.L.U.D.E.

@ axis11 am not getting no voltage on the 2 pin connector of the radiator wire side..
i checked for voltage on each 4 pin slots of the relay and am only getting one point energized i checked the ff. fuse
# 41(80A)
# 42(40A)
# 57 (20A)
#17 (7.5A) Underdash fuse relaybox.
and they are all good any other advice?
thanks alot guys really appreciate the help

dumplingz

thermostat?

black97civic

^ lol no. For whatever reason you not getting voltage to the relay. I don't have a diagram to say which fuse is in that circuit, but when you know that, the next thing to do would be check voltage at the fuse.

instrument

There is a very detailed faq for this issue, no idea why ya'll are wasting time.

axis11

How did you checked the fuse? You need to remove the 40 and 80 amp fuse and use an ohmmeter.
Which terminal is energized, left or right side(when you are in front of car and facing the car)?