Howdy, Stranger!

It looks like you're new here. If you want to get involved, click one of these buttons!

Ford Crown Victoria/Mercury Grand Marquis Climate Control



  • tgwilsontgwilson Posts: 2
    I have seen lots of messages about this subject. I just wanted to know if I can but a rebuilt one from some where.
  • I,m working on a 1997 Grand Marquis and the a/c clutch doesn't engage. I checked all my switches , and they check out good. I put twelve volts to the compressor and it works.(clutch), but I don't have 12 volts at the cotacts of the comp cutout relay. I do have 12 volts at the coil of the relay,and it works. I think its the E.A.T.C.M but I'm not sure. What can you advise me? or where can I exchange mine with one of your rebuild.
  • bobe21bobe21 Posts: 1
    I own 1999 Mercury Grand Marquis while traveling down the highway our Climate Control Unit totally quit working, you can get anything, at about the same time I noticed that I did not have and turn signals. We have checked all of the different fuses, all tested good. My Wife told me that the front the the climate control unit on the dash seemed to be warmer then the rest of the dash. Sue need some help.... I also own a 1997 Mercury Grand Marquis, can I exchange the units to see if the system will work or do you think it could short out this unit. Help Please.
  • Im new to edmunds site, my name is jack. i researched problem with EATC AC controll unit that would only blow air from the defrost vents and the remedy was to replace four .007 silicon "O" rings located on the accuator inside the controll module. Pull trim off by hand starting as passenger door. 4 screw hold unit in place. disconect 2 electric connections and vaccum lines then take unit to table and remove two star screws on back, lift up. That unit contains the four silinoids bend tabs at end and pull out accuator shaft, carefully not to lose the spring. Put new seals on. Reassemble. I just fixed mine for $8.00. The silicon "O" rings seem to work the best according to research.
  • dbj47dbj47 Posts: 3
    How do I contact you to get a EATC Module. I have a 2006 Grand Marquis with 35,000 miles and it just started switching the air to the defroster vent as I accelerate or go up a hill.

  • dbj47dbj47 Posts: 3
    Where are the two wiring harnesses located that have to be disconnected for a cold boot.

    thank you,
  • dbj47dbj47 Posts: 3
    Could I get a copy of the the pictures to hold vacuum harness up.

    Thank you
  • ginolenaginolena Posts: 2
    contact me at
  • I have an 07 grand marquis, same problem, but now it is blowing hot too. Checked the door actuator and it has small amount of vacum. I have just over 90,000 miles when door stopped moving . Now 102,000 and its blowing heat to on 90degree days. I found a dealer on ebay who rebuilds your eatc for 79.00
    and free shipping. Money is tight right now, was wondering if Bigmercs fix would work for me too.
  • ron30096ron30096 Posts: 2
    Hi joveto, simple fix,but only temp, i used a pair of needle nosed vise grips and clamped off the heater hose going into the heater core, no more 9000 degree heat into the car,I plan to put an inline shutoff valve in the hose in order to not have to rip the dash out to fix, my 98 has 200,000 miles on it and runs great
  • efan1efan1 Posts: 1
    Where can I get a picture or diagram of the EATC head units working mechanisms. I would like to try to repair the O-ring failure as mentioned in post #108. Several requests for pictures have been made in this forum, but I cannot find any responses to those requests showing pictures, etc.
  • I truly thankyou for the advice, it worked for me today. I was quoted to replace the head unit and labor 600.00 so what a savings! Again, thankyou for the answer.
  • I have 96 ultra high quality silicone "O" rings (out of 100) to give away; I only needed 4 to fix the EATC. The Ford dealership quoted me over $1000 (tax included) to "fix" the problem. The "O" rings from McMaster-Carr, part number 9396K12, cost less than $10 (UPS included). I am NOT a mechanic but found lots of photos and instructions online. Total time: 2 hours from start to finish and LOTS of cold air (90+ temp here). :) Same fix for 1998-2008 Ford/Mercury.
    I just need a self-addressed/stamped envelope and the "O" rings will be on their way. After all, I saved about $1000!
  • shadetree9shadetree9 Posts: 6
    edited August 2011
    Thanks much for the link to the photos. I took my climate control apart at least three times and could not find the o rings. I was taking the whole activater off and the o ring was not in there. Now I know to take the plunger out of the other end. It is working well so far. You really helped and saved me time money and torment.
    Another post offered me free 0 rings from the master sargent in message 118 and he sent them in the mail so I did good. You're a great american
    Thanks again 08 grand marquis
  • rog1015rog1015 Posts: 3
    edited August 2011
    A/C and blower work well on short trips. When I run out about 200 miles or so, unit starts to blow hot. 20 minutes or so later it returns to cold (I turn off A/C when it gets hot and run with windows down). Blower is fickle also ie, high becomes a trickle of air vice the full blast. Sometimes there is little air flow and it is hot....
    I'm not a spring chicken and it's hot down here in Texas!!!!! Any help greatly appreciated. The dealer finds no fault...Can not recreate issues with the car idling in garage...
  • wwestwwest Posts: 10,706
    If your engine coolant tends toward overheating, NOT actual overheating, the A/C compressor will be disabled automatically.
  • rog1015rog1015 Posts: 3
    edited August 2011
    Just got Merc a few weeks ago. have not noticed any indication of overheating but I will flush coolant and see if that helps-was planning on doing that anyway.
    thanks for the fast response!
  • mgb8mgb8 Posts: 1
    Hello all. Question, I have a 2008 ford crown vic, recently my air conditioning has starting switching from defrost to floor, if I take my foot off gas or place in nutural it goes back to dash vents.. Anybody offering any advice, dealer says it is control head and want 600.00 for part and 300 labor, there has to be a fix for this out there, with soooo many crown vics on the road as taxis, and etc. Please help. ebay has an ad for sending unit off for 75.00 who person says he has developed a fix for this? Please help.
  • You can get a re-manufactured part for about 340.00. It take 4 mins to replay yourself. It is the easy thing I have done. I purchased the part at o'reilly's auto part but you can get it at any of the major parts stores.
  • Okay, I'm at wits end...2000 Grand Marquis that I love, except:

    My a/c blows warm, and after some research I checked that my a/c clutch is engaging and the line in the engine compartment to the (accumulator tank?) gets COLD telling me my freon is I started looking into the blend motor door/actuator, since that's very common issue I understand.

    Since I didn't want to remove my entire Panel and pull the dash back, etc...I pulled my Glove box, and cut a small viewing "hatch" into the plenum chamber to view the blend door operation. I can see the blend door and it operates fine. When I put the control on "Max Air" it swings one way, when I put the control on "Floor" (heat) it swings the other...indicating the door is being actuated, and is operational.

    What the heck do I look at next?
  • Hi crownvicfan,
    I sure would like to take advantage of your selfless offer to share your "O" rings, but I dont know how to contact you. My EATC is sitting on my tool bench waiting for me to bring it back to health. May I hear from you?

  • wwestwwest Posts: 10,706
    "..when I put the control on "Floor".."

    That statement implies that you're looking at the outflow direction control vane/damper/door, not the blend door. The blend door moves in response to the system temperature setting, MAX cooling vs MAX heating.
  • w9bagw9bag Posts: 2
    My 2003 CV vacuum system bleeds off immediately when I shut the engine off. It causes no problem with the operation of the EATC, but with all other cars that I have owned, the system
    stays loaded with vacuum, allowing for 3 or 4 cycles of various settings before the vacuum
    canister is depleted. Is this something that I should be concerned about?
  • wwestwwest Posts: 10,706

    Other than being concerned about what else, how else, Ford might have cheapened the vehicle design. Most modern, more modern, cars use electrical servo motors that are always disabled likewise.
  • You need new "o" rings in the control head. About $1.00 and 2 hours of work. You can eemail me
  • crownvicfan- have a 2005 merc g.m. not changing out of defrost mod. Would like to get 8 of the o-rings if you still have any. ( in case, like so many things in life, so,mething goesw wrong on the first time) Thanks, dodger don
  • My 2008 Grand Marquis LS has the automatic climate control (set temp and climate control system adjusts to maintain the temp). Recently a problem: Over a 24 hour period the blower speed would drop out, i.e. one moment would be running at speed (including a manually-set speed) and then would drop to zero. Started infrequently, then became more frequent, then no blower at all. ETAC passes the self-test.

    I'd like to check the blower resistor and/or HVAC Blower Motor Control Unit (a MOSFET), but I'm not sure if my car has one or the other, or both.
  • Heater/ac not working. Don't have any success running EATC self test. Unit lights up, but doesn't start any test so far as I can see. Should I try a cold boot? Any other suggestions before I try to get a replacement unit? I've been hearing a sound like a vacuum actuator trying to move after starting the car. Any connection? And where do I get a rebuilt unit? Thanks for your help...
Sign In or Register to comment.