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Cooling fan temperature switch question

Got a REALLY off-the-wall question for all you VERY knowledgable folks:

I've got a 1986 Mercury Cougar XR7 Turbo 5-speed that I'm the second owner of.  In 1992, the original owner had the engine replaced (long block).  Now, the cooling fan sensor/switch (the thing that screws into the top of the block to turn the automatic cooling fan off and on according the engine temp) has gone out and we 've tried two times to get the right one ordered that will fit the car but, no luck.  Is there some code or something on the enginre that we could give to the parts place or Ford dealership that would enable them to order the correct part?  Right now, my husband's got the fan wired straight to the battery so we can have it off when the weather's cold (so I can have HEAT) but, if I'm going to be in any traffic, I have to put the hood up and hook it up ;-(      Thanks again for you assistance!!
1986 Mercury Cougar XR-7 Turbo-charged 5-speed.
Owned 22 years.

Cooling fan temperature switch question

Reply #1 –
The switch you are looking for is labeled "Electric Fan Switch" in the diagram. Unfortunately the fan controller module and not the switch is probably the problem.

NAPA has a fan switch on their web site. Does it look right?
http://www.napaonline.com/Search/Detail.aspx?A=ECHFS125_0182396574&An=599001+101986+50046+2046012

Unplug the connector from the fan switch and with the key on and the engine not running, grounding one of the wires should make the fan run. The diagram shows the wires both the same color, so you may have to try them both.

Cooling fan temperature switch question

Reply #2 –
I have the same car and problem, I would second the controller being bad. I am contemplating wiring in a toggle switch to run it but as of this moment it runs constant. Post what you find out or do as I would be very interested in the cure.

Cooling fan temperature switch question

Reply #3 –
Thanks for the info, SoftTouch!  I've printed out your diagrams and now it's back to the old drawing board! ;-)  That NAPA part doesn't look like the sensor that's in the top of my block.  What I'm really wondering is - since the new engine was put in the car in '92, if maybe we need to be trying to get parts for a '92 instead of an '86.  Sorry if this is a dumb question but you are dealing with a woman here who knows Pontiac 350s inside and out but when you get into all this electrical and computerized stuff, I'm pretty well lost ;-(
1986 Mercury Cougar XR-7 Turbo-charged 5-speed.
Owned 22 years.

Cooling fan temperature switch question

Reply #4 –
ask for the ECT  and get the brass body one.. it installs between the #2 and #3 runners in the lower intake, it will take a 1 inch deep well socket
NAPA Part Number MPE TS4060SB

when this fails the ECU will default to thinking the temp is -40* and you will run pig rich and blow black smoke

the ElE fan controller is located under the glove box, it is brown, appox 2W x 4L x 4T and has a gang plug with about 8 wires (appox 40 bux at the parts store) it als so th same one that is used on the 88 mustang 2.3 cars

NAPA part Number  TEM 207707

NAPA is a bit high on them, $60 or $80 

Hope this helps
1985 TC (yet another one) Fully loaded
has 225k mile  still with the factory head gasket






84  Turbo ranger  Daily driver  ($800.00 Ebay deal)
          volvo FMIC and more getto rigging than the law should allow

Cooling fan temperature switch question

Reply #5 –
Quote from: CougarGal;315411
That NAPA part doesn't look like the sensor that's in the top of my block.

That would be the ECT (engine coolant temp) sensor on top of the block. For 86 they had a separate fan switch on the lower left side of the block in front of the oil filter. See the diagram.
Quote
  What I'm really wondering is - since the new engine was put in the car in '92, if maybe we need to be trying to get parts for a '92 instead of an '86.

If you don't have the fan switch on the engine you may be right, and now you have a mystery on your hands.
Any chance you can contact the original owner and find out what was done?

In 87 Cougars and T-Birds went to a two fan system. One fan is controlled by the A/C pressure switch. The other controlled indirectly by the ECT sensor.
ECT sensor-EEC (electronic engine control)-ICM (integrated controller module)-fan motor.

When you say they installed a long block, it implies they bought a new or rebuilt engine. Question is did they upgrade the electronics or adapt the new engine to the old electronics?

In either case, you can tell if the ECT is working by pulling codes.

Cooling fan temperature switch question

Reply #6 –
Soft touch is correct the ECU temp sensor has nothing to do with fan control on the '86, sensor should be in lower section of intake as pictured...

Here's a thought, possibly a sensor for the 2.3 '86 Stang would be the same??? Sensor is in same location...

Look like this(pict is big)??? This is the one I have from a Stang... I'd think the fan circuit would be similar, if not same on the 2.3T(I'll pull my '86 Stang EVTM and compare)...

http://members.pen 15s.net/turbocoupe50/2.3fansensor.jpg

EDIT '86 NA 2.3 Stang uses basically same circuit but does show the fan sensor directly grounded, vs sharing a common ground with the fan the Cougar is pictured as having... In that case it probably is a different sensor vs one for Stang...

Another thought, IF your AC isn't working, all you have to do is jump out the AC low pressure switch and the fan should run in Max, Normal, or Defrost modes... Unplug the AC compressor electrical connector if it is still connected... If it runs in this mode the fan controller is OK...
 

Cooling fan temperature switch question

Reply #7 –
Thanks everyone!!!  I'm thinking that we may have been told that we needed to replace the wrong part to get the fan working automatically again ;-(  as we've been trying to find the one that goes on top of the block rather than the one down by the oil filter.  Maybe that one will be easier to find at our local parts place.  Will keep everyone posted once we know for sure!
1986 Mercury Cougar XR-7 Turbo-charged 5-speed.
Owned 22 years.

Cooling fan temperature switch question

Reply #8 –
Quote from: softtouch;315430
That would be the ECT (engine coolant temp) sensor on top of the block. For 86 they had a separate fan switch on the lower left side of the block in front of the oil filter. See the diagram.


I just went and looked at a 85 TC and a 86 Turbo coguar... Neither has this switch you speak of, nor a point to mount one from what I can see, ( I looked at several other turbo 2.3 blocks and did not see one either.

Now above and behind the oil filter, is the temp sender for the gauge on the dash.

also I want to say its the same ECT for the NA and turbo 2.3 along with most all 80's Fords with EFI and Ele fans
1985 TC (yet another one) Fully loaded
has 225k mile  still with the factory head gasket






84  Turbo ranger  Daily driver  ($800.00 Ebay deal)
          volvo FMIC and more getto rigging than the law should allow

Cooling fan temperature switch question

Reply #9 –
Quote from: softtouch;315385
The switch you are looking for is labeled "Electric Fan Switch" in the diagram. Unfortunately the fan controller module and not the switch is probably the problem.


x2, had this issue with my mustang and it was the fan controller box thing under the dashboard.
i never replaced it because the dealer wanted a mint for one and just ran a toggle switch to the battery.
the funny part was i had the wire(house wire at that) and a led washer toggle switch in the car already for some reason :/
"Beating the hell out of other peoples cars since 1999"
1983 Ford Thunderbird Heritage
1984 Ford Mustang GT Turbo Convertible
2015 Ford Focus SE 1.0 EcoBoost

Cooling fan temperature switch question

Reply #10 –
Just ordered my replacement fan controller from Rock Auto $24 shipped to my door. AutoZone wanted 30 and had to order also, and advance was 33.

Cooling fan temperature switch question

Reply #11 –
Quote from: Dansbirds;315503
Just ordered my replacement fan controller from Rock Auto $24 shipped to my door. AutoZone wanted 30 and had to order also, and advance was 33.


Is this the box under the glove box?  If yes, I may just order one from Rock Auto just to see if it fixes the problem.  You don't, by any chance, have the part number for Rock Auto?
1986 Mercury Cougar XR-7 Turbo-charged 5-speed.
Owned 22 years.

Cooling fan temperature switch question

Reply #12 –
Yes the one behind the glove box. Here is there info http://www.RockAuto.com
service@rockauto.com
1-866-ROCKAUTO (1-866-762-5288)
(608) 661-1376
Fax: (608) 836-5694
AR247 is the part #

Cooling fan temperature switch question

Reply #13 –
Quote from: Dansbirds;315532
Yes the one behind the glove box. Here is there info http://www.RockAuto.com
service@rockauto.com
1-866-ROCKAUTO (1-866-762-5288)
(608) 661-1376
Fax: (608) 836-5694
AR247 is the part #


Ordered it!  THANK YOU! THANK YOU! THANK YOU!!  Every time I entered radiator fan switch, I was only give the ones that screw into the block.  I'd have NEVER found this one ;-(
1986 Mercury Cougar XR-7 Turbo-charged 5-speed.
Owned 22 years.