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    #1

    A/C Fan

    I have the ATC heat and A/C. The 3 fan speeds all work if I put the switch in each of the 3 settings. It will only work in low speed if I put it in auto. The fan is new, I get heat ( in the Floor pos. the fan will stay off untill the temp comes up) and the A/c works as it should.
    Any ideas?
    89 CV LX 225/60 x 16 tires, CC819 rear springs, Front & rear sway bar, trans & PS cooler from 90 cop car. KYB shocks, F-150 on rear. Dual Exhaust w/ H pipe. Dark brown door panels, carpet, steering wheel, trim parts from a 87 Mer GM. Power front buckets from 96 Jeep Cherokee. LED'S front & rear. 3G Alt from a 97 Taurus wagon 3.0. Electric fan. Rear axle from a 97 PI 3.27 with disk brakes. Headlight relays.
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    #2
    Mabey it's a relay One time man compressor clutch was not spinning it was the relay that was the problem

    1989 mercury grand marquis gs / 2014 ford focus s daily driver
    302 lopo with ho upper/ aod with trans go shift kit
    k code 3:55 posi rear/big brake swap tow package car

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      #3
      Glen, the speed of the fan in auto mode is determined by the difference between the ambient in-car temperature and the temperature you set with the dashboard controllers - have you tries puttin it to 65*F when it's really hot outside, or 85*F when it's real cold? oemally in that type of situations the fan spins at it's fastest speed, and as the in-car temperature approaches the one set by you it will slow down.

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        #4
        Yes I have tried the high and low end of the temp range. All I get in auto is low.
        89 CV LX 225/60 x 16 tires, CC819 rear springs, Front & rear sway bar, trans & PS cooler from 90 cop car. KYB shocks, F-150 on rear. Dual Exhaust w/ H pipe. Dark brown door panels, carpet, steering wheel, trim parts from a 87 Mer GM. Power front buckets from 96 Jeep Cherokee. LED'S front & rear. 3G Alt from a 97 Taurus wagon 3.0. Electric fan. Rear axle from a 97 PI 3.27 with disk brakes. Headlight relays.

        Comment

          #5
          Beats me man, dunno exactly how the fan is tied with the ATC. Whatever controls the speed of the fan based on the difference between the dashboard controls and the ambient temp sensor readings, that is probably your problem, maybe someone else will get a light flashing in their brains from that and chime in?

          Comment

            #6
            There is a fan speed controller attached to the top of the ATC blend door servo. If you pop the glovebox, you can see the gold can back there with the clear vacuum hose. Thats the blend door servo. Looking at the EVTM I have, there should be an electrical plug on or near the front of that can. Thats the speed controller. Somehow, this thing is connected to the blend door servo, I'm assuming with a linkage rod of some sort. Possibly either the speed controller is bad or the linkage between the blend door and the fan speed controller is messed up. I cant say how accessible that mess is short of pulling half the dash apart though. Its also possible that your fan resistor is toast. The fan resistor can be found on the side of the evaporator case kind of behind the left corner of the intake. It has a 5 pin plug going to it, and it looks to be a total pain in the rear to change.

            Happy hunting.
            86 Lincoln Town Car (Galactica).
            5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

            91 Lincoln Mark VII LSC grandpa spec white and cranberry

            1984 Lincoln Continental TurboDiesel - rolls coal

            Originally posted by phayzer5
            I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

            Comment

              #7
              Originally posted by gadget73
              There is a fan speed controller attached to the top of the ATC blend door servo.
              My car had this problem. This is exactly the right answer! On the servo is a switch. A linkage connects the switch to the servo which moves the blend door. The switch is a three position switch, just like on your dash, but in this case, the servo changes the position is response to the difference in temperature (between actual and the setting on the ATC).

              In my case, I tried to find just the switch alone, but could not, and it seemed that the only solution (from Ford) was to buy a new servo/switch combo. So, I just took the switch off the servo, and re-installed the servo. So, my ATC does not work in AUTO, but what the heck.

              Removing the servo is easy, and DOES NOT require a dash removal. I removed the stop bracket on the glove compartment door to let it swing down out of the way. I recall two nuts (or screws?) holding the servo/switch assembly to the plenum. It is actually very easy, and quite quick, too.

              If you find a source for the switch alone, I'm interested. I would have searched the boneyards, but we only have one in this area, and it only has one Towncar.

              In my case, not only did the switch fail, but failed in such a way to prevent the servo from moving the blend door - so not only didn't the fan work on AUTO, but there was not much heat, either. Removing the switch cured both problems.


              HO with Explorer Cam, Electric Fan, Cop Sway Bars, Dual exhaust with no mufflers, 15x7" American Racing; 215/70R15's front, 255/60R15's rear, 3.55's with Trak-Lok.

              Comment

                #8
                Good to know man. I've never tried to get it out, nor have I ever looked very close so I wasn't sure if it was a horror or not. Only time I've ever really seen the thing was when the dash was torn half out for a heater core replacement anyway. The EVTM doesn't really detail how it comes out, and I didn't dig into the shop manual for it. I was just going based on most anything else to do with the HVAC systems on these things that its a real pain in the ass to deal with.
                86 Lincoln Town Car (Galactica).
                5.0 HO, CompCams XE258,Scorpion 1.72 roller rockers, 3.55 K code rear, tow package, BHPerformance ported E7 heads, Tmoss Explorer intake, 65mm throttle body, Hedman 1 5/8" headers, 2.5" dual exhaust, ASP underdrive pulley

                91 Lincoln Mark VII LSC grandpa spec white and cranberry

                1984 Lincoln Continental TurboDiesel - rolls coal

                Originally posted by phayzer5
                I drive a Lincoln. I can't be bothered to shift like the peasants and rabble rousers

                Comment

                  #9
                  Thanks I'll look at that in tne next few days. I don't really care if the Auto works, but heat would be nice.
                  89 CV LX 225/60 x 16 tires, CC819 rear springs, Front & rear sway bar, trans & PS cooler from 90 cop car. KYB shocks, F-150 on rear. Dual Exhaust w/ H pipe. Dark brown door panels, carpet, steering wheel, trim parts from a 87 Mer GM. Power front buckets from 96 Jeep Cherokee. LED'S front & rear. 3G Alt from a 97 Taurus wagon 3.0. Electric fan. Rear axle from a 97 PI 3.27 with disk brakes. Headlight relays.

                  Comment

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