engine cooling fan won't come on (1995 mustang)

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the paper clip is for testing.. having it in ensures that the ecm is being told that
it is at max temperature..
by unplugging it, it would read -40f degrees..... by inserting the paperclip you are now telling the ecm that its 300f+...
 
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U are referring to the one circled in red, the sensor, not the connector.... correct?

When I was looking at it yesterday, it is not the new one that I installed, they put another new one at the repair shop...so it's been replaced twice........but If U think it could be the sensor I am willing to try replacing it again.
 
For some reason, my does the exact opposite (inserting a paper clip).

If i put in the paper clip it does nothing. however if I turn the car on, unplug the wire and wait 5 secs, my fan comes on.

I had the car running for about 20 mins, my aftermarket gauge reached 240* before I unpluged the connector and sure enough, the fan came on and got it back down to about 200*. Any thoughts on this? or is this common when the car is acutally running. Your test was meant to be done on a non-running car. I tried it and it did nothing.

Thanks.
 
ok there are many different problems with a cooling system,
if you read from the beginning you would understand the theory for the paperclip
or jumper wire.. if you try to do this test with the defrost on it defeats the purpose..the defrost uses the a.c. system to pull the moisture off the windshield.. so no matter what temperature the coolant is at, turn the def; on and the fan will come on..
...this is a very limited and quick way to determine if a c.t.s
is not functioning..obviously checking the resistance with a multimeter at more than one specific temperature is the right way..
only because of torres situation of already having other components checked did i go the quick route of having him do checks of the system..
i can tell you the c.t.s. sends a signal to the ecm stating the temperature the engine is at from there the ecm controls the fan to come on and off.
the paper clip is for testing whether the ecm will respond to a maximum signal
say 300 degrees...
 
I'm wondering if the CTS worked for you? My son's car is having the same problems. We replaced the thermostat, radiator, alternator & water pump in Nov. The other day, his car overheated. I determined the fan was not coming on. I have checked the fan with the AC on & off. It dosen't do anything. We replaced the fan motor today, still nothing. It sounds like you are having the exact same issue. I'm also in Texas & need to get this fixed soon.
 
I'm wondering if the CTS worked for you? My son's car is having the same problems. We replaced the thermostat, radiator, alternator & water pump in Nov. The other day, his car overheated. I determined the fan was not coming on. I have checked the fan with the AC on & off. It dosen't do anything. We replaced the fan motor today, still nothing. It sounds like you are having the exact same issue. I'm also in Texas & need to get this fixed soon.

Have you checked the motor fan relay? ;)
 
I am having the same problem with my 2000. My fan doesn't come on with the A/C on at all. We ran some wire directly from the battery to the fan and it started right up, so i know the fan motor isn't bad. We checked the fuse and it's getting power, but somewhere between there and the fan is the problem. I bought a coolant temp sensor last night to try that and see what happens. The bad part is that on my 2000 the coolant temp sensor is in a sort of awkward spot on the manifold. I have the same question as agrigar, where is the motor fan relay? All i have in the fuse box, is a fuse LOL, no relay? According to Hayne's the Coolant Temp sensor and ccrm are likely candidates. My a/c works just fine while driving, but blows hot at idle. Anybody got any other suggestions for me by any chance? Thanks.
 
tried to jumper it with the paperclip to no avail. fan still doesn't come on? I'm soo sick and tired of this car, i swear. what should i move onto next? If me and my buddy that owns a performance shop can't figure out how to fix it i'm just gonna put in an aftermarket fan and wire it up instead of spending tons of money at a shop that will keep trying different things and never fix it like the other guy on here. thanks for any help you can offer.
 
you need a coolant temp sensor my friend..
the reason for the paperclip is that you are actually telling the computer the car is
running at 300 degrees..it is obviously NOT the computer otherwise it wouldnt have turned on.. trust me c.t.s is your problem..
dont get it from autozone, for 2 more dollars get one from napa..
everything should work properly after its installed..

i agree if you unplug the ECT sensor and fan goes on the sensors is bad telling the eec that engine is always cold and fan will not come on.
 
I bought a 94 mustang from a friend with a aftermarket fan and a toggle switch (not ran the greatest in the car but works lol) he said something about it melted the fusible link on the original fan so he bought a aftermarket and slapped it in there now I would like to put the right fan back in but I cant find anything about a fusible link for the fan I know about the relay and regular fuse but is there a fusible link for this car or is he just full of crap lol. is there a way to test the temp sensor to make sure its telling the ecm to kick the fan on
 
the fan is controlled through the ecm which sends power to the relay to turn the fan on. the ecm takes the signal from the coolant temp sensor to know what temp the fan needs to come on at.
by jumping the plug to the c.t.s. with a cotter pin, basically tells the ecm
its at full temperature.......if it will not turn the fan on, use a test light at the plug to the fan to see if it is getting power...if it is it would be between the plug and
the fan, if not you have to work backwards and check fan, relay, ecm, cts,...
the most common problem ford had was the plug connection to the fan itself.
that is why they recalled, for a fan resistor install between the plug to the fan and harness..why? because the fan plug was melting, overheating, causing the three wires encased in the fan plug to melt the plastic that seperates the 3 wires.
causing the ground wire and the power wire to touch.. result ..fan inoperative..
it is highly misdiagnosed because you cant see the melted parts of the plastic until you actually unclip the plug and look into it.
i have replaced quite a few fan assy.. since they started having this problem in
1994..
my 2000 wire harness only has two wires coming out but three posts on the terminal, one just goes into a dead hole on harness. I have probed the wires at fan plug in and it still wont come on, I've also jumped at the cts and nothing. On mine the cts is plumbed into a union and into the block, kind of weird cause its not like any I've seen.
 
why cant i get mine to do anything? Ford played a few swapping games between the late 90's and even my 2000 model is different. ive tied the paper clip and got nothing, i used a test light and have no power to it either, Im at a loss seeing how i need my fan to work, and cant find anyone to show me where a relay is for the 2000 model 3.8