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View Full Version : No cooling fans..help

Redbrd
03-01-2008, 11:01 AM
Noticed yesterday my cooling fans werent kicking on,even when I turned on the ac they still didnt come on,I swapped around the relays,nothing,fuse is good,could it be the switch on the block near the water pump??I was thinkin no because they dont come on with the ac at all.
red_z28
03-01-2008, 11:23 AM
Did you let the car come up to temp first?
Redbrd
03-01-2008, 11:32 AM
Yes the car actually got up to the last white mark before the red,i hate seeing it that high,we have cool temperatures now but it will warm up soon and stop and go traffic im afraid will be a problem with overheating.Oh and I bled the system of air also..
red96tam6
03-01-2008, 12:45 PM
it would be weird for your fan motors to both go bad, but it isn't impossible, it's a little more likely that your relay is bad, since when you swap em, nothing happens.
red_z28
03-01-2008, 12:52 PM
easiest way to tell if theyre working is to disconnect them, ground out the ground side, and extend a similar size wire from your + side and touch the battery with it. It should turn on. If you cant figure out how to do that, shbox has a write up.

Heres a schematic of the fan: http://shbox.com/1/fan_schematic_1995.jpg

Here is where to wire in a switch to control your fans using a switch: http://shbox.com/1/fan_schematic_1995.jpg

Basically I think you could just use a jumper wire from your + side battery terminal to the highspeed or low speed wire...You could just back probe the H and J by using a metal pin or clip. This way doesn't damage the wires if you're careful.

Heres what a T pin looks like. They work great for back probing : http://www.pldaniels.com/flying/balsa/images/t-pins.jpg


And yes.. your relay could be bad if this test works.
keenan
03-01-2008, 12:53 PM
Unplug the fans run a wire from battery to each & this will eliminate burnt motors ,(doubt both burnt at the same time) there are 3 relays that control the fans get'em fron oreily auto not a napa store same relay 2x the price.Get out the old gm manual nothing much i'm sure but don't get that motor hot again.I belive factory kick on temp is set at about 235-240deg.Good luck.
Redbrd
03-01-2008, 01:50 PM
Ok thanks for the input,its greatly appreciated,Ill try running seperate power to the fan motors to see if they are burned out,if they are good ,Ill see if changing out the relays works.
AR15 guy
03-01-2008, 01:53 PM
Disconnect the connector at the WP and see if they both kick on.
Redbrd
03-01-2008, 01:56 PM
If I disconnect from the waterpump ,they should both come on while motor is running?
shoebox
03-01-2008, 05:12 PM
easiest way to tell if theyre working is to disconnect them, ground out the ground side, and extend a similar size wire from your + side and touch the battery with it. It should turn on. If you cant figure out how to do that, shbox has a write up.

Heres a schematic of the fan: http://shbox.com/1/fan_schematic_1995.jpg

Here is where to wire in a switch to control your fans using a switch: http://shbox.com/1/fan_schematic_1995.jpg

Basically I think you could just use a jumper wire from your + side battery terminal to the highspeed or low speed wire...You could just back probe the H and J by using a metal pin or clip. This way doesn't damage the wires if you're careful.

Heres what a T pin looks like. They work great for back probing : http://www.pldaniels.com/flying/balsa/images/t-pins.jpg


And yes.. your relay could be bad if this test works.

You definitely DON'T want to put + battery to H or J. You are likely to burn someting up. The potential needed on the wire(s) to activate the relay is GROUND.
AR15 guy
03-01-2008, 05:30 PM
Yes if you disconnect that wire the fans will run anytime the key is on. Its a safety feature of the car.
red_z28
03-01-2008, 10:10 PM
You definitely DON'T want to put + battery to H or J. You are likely to burn someting up. The potential needed on the wire(s) to activate the relay is GROUND.

woops...how dumb of me.. I actually followed the write up on shbox and did the switch for them too:screwy:
Redbrd
03-02-2008, 12:37 PM
Ok,disconnected from waterpump,started car and one fan did come on,so does this mean its the relay?
shoebox
03-02-2008, 01:59 PM
Ok,disconnected from waterpump,started car and one fan did come on,so does this mean its the relay?
No, the relays have to be working for the fans to come on.
You say the fans don't come on with the a/c. Is the a/c in working order? How cold is it where you are? Can you verify with a scanner that the fans are actually being commanded on when you think they should be on?

BTW, the year of your car needs to be in your sig.
Redbrd
03-02-2008, 02:05 PM
The ac is fully functional,today its around 70 here,I had as part of my program for fans to come on at 195.
Redbrd
03-03-2008, 07:51 PM
Ok,disconnected from waterpump,started car and one fan did come on,so does this mean its the relay?

So did anyone notice that I said only one fan came on? Would that be what was supposed to happen or should both come on?:dontknow:
shoebox
03-03-2008, 11:23 PM
Both should come on.
cadeMFjohnson
03-04-2008, 01:47 PM
i have the same year t/a.. its kinda hard to even tell if the fans are on if u got big hands like me lol. u cant see the back of the radiator its so cramped. gotta wiggle ur bear claw in and feel for wind. it sucks...


or be a hardass and stick a knuckle into the fan.. its plastic but it hurts a b*tch!