View Full Version : Cooling fan not turning on

05-20-2003, 02:59 PM
Just drove the car for the first time since winter and I noticed that the cooling fan isn't turning on on its own. I replaced the thermostat and still nothing. I think it first started when I was replacing the harmonic balancer during early winter. Any idea what this could be? I've just bin driving with it always on recently, but this creates that nasty 'check engine' light on my dash. THanks for all your help.

05-20-2003, 03:28 PM
I've had that problem for 2 yrs (&still running)and i've traced it to the "Integrated Relay Control Module" (not sure though) I went to replce it for 350.00$ Canuck Bucks and would you beleive I bought the olny one in Canada and it was faulty, can you beleive that!!!!Sh#@ty deal eh!!!! I'm in the midst of getting my money back for it though from Ford Of Canada which is a miricle in itself!!!!(lol)

If you figure it out please let me know!!!!!

05-20-2003, 03:29 PM
I forgot to tell you, I get around it by turning on my A/C!!! Heh, it works:D

05-20-2003, 03:32 PM
I have the same problem. The book says that if the fan works when you jump it out to the battery then it can only be 3 other things. the intergrated relay control module,the E.E.C. or the coolant temerature switch.
I have a new intergrated relay control module on my 90 S.C. so thats not it so I guess I will go with the cheaper of the 2 and go buy coolant temperature switch.
Like you my car sat for about a year so I dont know whats going on with her. If you find anything out let me know.

05-20-2003, 04:09 PM
Where is the coolant temp. switch??? I know the sensor!! $16.00 at Canadian Tire! Not bad. I put 160 t-stat, new sensor, tried to change my relay control module(read above post), so I'm still maybe guessin mines in that(IRCM)but i hope not! I wonder if there's a test you can run on that??? I 've tested my EEC and its fine, in that respect anyways!!! I'm sure I'll get it in time, in the meantime the A/C is good enough!!!!

05-21-2003, 07:57 AM
Remove the electrical connector from the IRCM and locate which is pin #14. Cut the wire into (leave enough coming out of the connector to solder or crimp back). Plug the connector back into the IRCM, if the fan comes on, the IRCM is good for the low speed fan.

Now, locate which is pin 17, stick a pin into the wire while it is connected to the IRCM and then run a ground jumper wire to the pin, the high speed fan should come on.

Cutting the wire to pin 14 allows the low speed fan relay to send power to the low speed side. Grounding pin 17 allows the high speed fan relay to send power to the high speed side.

This is how I trouble-shot my '90 SC. I do not know how many years these pins stayed the same.

05-21-2003, 10:44 AM
Thanks for your help, but I have 1 question about this???

When you do this to both wires, which speed will come on??? From the way that it sounds, both speeds will work? If I do this to my IRCM, and it makes my fan work, does this mean my IRCM is faulty?
Right now I get around it w/ the A/C & a 160 t-stat, and i'm pretty sure thats just a low speed!!

Thanks again for the info!!!!!!:D

05-21-2003, 10:52 AM
The fan motor on our cars has two seperate windings. One set of windings is for low speed. The other set is for high speed.

When both windings are energized, the current draw is very high, and will lead to premature failure.

So you don't want both energized at the same time.

What was described for you was how to test them. If you get a fan with the A/C on, then you are getting the low speed fan. If you want to test the high speed, simply ground pin 17 and turn the key on. You should get high speed fan.

For the most part, the temp setting for the High Speed fan is set so high, that you would only see it turn on automatically in the most severe heat. That is why you might see a diagram mentioned in some posts about a different way to wire the fans to have them come on a little lower. We know that heat is bad for our cars so people have prefered to turn the fans on at lower, more sane, temperatures.

05-21-2003, 06:48 PM
I was having that same problem, all I did was replace the coolant tempature sensor. Now the fan works fine.

06-04-2003, 03:33 PM
K. Right now I just have some sensor near the air intake tube pulled out so the fan is on all the time, which is just fine with me. But it leaves the brightest check engine light on in my gauge cluster :( . So I tried turning the ac on and the fan still wouldn't turn on. I think I'll now try that coolant temp sensor replacement thing. I'm just wondering where this thing is located exactly?

06-04-2003, 08:03 PM
find one that has the brass tip on the end. dont buy the all plastic one as it will burn out. that was my problem until i put the brass tipped one in and ive gone three years problem free with my fan.

06-05-2003, 03:30 AM
Where is it located???

06-05-2003, 01:11 PM
That's the one I have yet to figure out myself.

Could someone point out where both coolant sensors are and which is what?

One is by the thermostat and is for the gauges, as I understand. I just haven't figured out where the EEC sensor is at.

06-05-2003, 01:25 PM
As U face the engine there is a sencer located in a coolent line just to the left of the Blower snout. This sencer has 2 wires going into it. This is the sencer that sends a voltage to the Puter. The Puter uses this signl to turn on the fan.

The sencer for the guage is to the right mounted in an intake water passage and has one wire attached.

06-05-2003, 04:08 PM
Does anyone know where I can buy a integrated relay control module online?

06-05-2003, 07:06 PM
go to the "want to buy forum" and tell them the year and what you want and someone will send you a personal message or e-mail you with a price.