a/c blower vents not switching

Asked by Apr 18, 2011 at 11:42 PM about the Mercury Grand Marquis

Question type: Maintenance & Repair

I AM HAVING A PROBLEM WITH THE A/C BLOWER NOT BLOWING OUT THE FRONT VENTS. IT IS STUCK ON DEFROST.THIS HAPPENED WHEN IT WAS STILL  UNDER WARRENTY ABOUT FIVE YEARS AGO .I WAS DRIVING ALONG AND THE RADIO AUTOMATICALLY SWITCHED STATION AND THE BLOWER STARTED SWITCHING BETWEEN THE FRONT VENTS AND THE GOING TO DEFROST THAN TO THE FLOOR.VENTS. THE DEALER HAD TO REPLACE THE A/C MODULE BACK THEN IT WAS VERY ERRATIC .NOW IT IS STUCK ON BLOWING OUT THE DEFROST AND ALSO THE FLOOR VENTS. HAS ANYONE ELSE EVER HAD THIS PROBLEM? THANKS FOR ANY HELP.

10 Answers

eather the module has gone bad again,also check vac lines under hood or the heater control has gone bad,doubt the raido has anything to do with it.

28 of 28 people found this helpful.
155

My 2007 MGM is at the Ford house right now getting fixed for this same problem. This is the 3rd time. My radio wasn't affected though. Ford paid for the first repair under factory warranty. Luckily I purchased extended bumper to bumper plan. $100.00 a pop. But it sure beats paying full price. Over $700.00 for part. Plus labor. Yikes! A friend has an 05 super heavy duty F350 and it's heater/ac unit has done the same thing 3 times as well. Looks like a vendor issue with this particular part. Good luck with your car.

9 of 9 people found this helpful.
500

The EATC module is at fault. These can be repaired or replaced on eBay pretty cheap. The guy who did mine was eatc-man on ebay. He has a store Ford EATC and more on eBay as well. He offers both repair and replacement. Here is the link http://stores.ebay.com/Ford-EATC-and-more.

47 of 47 people found this helpful.
580

I have the same problem on my 2005 MGM. It makes a growning sound when I start the engine, as if something is stuck or jambed. I hope it is not the mode door being broken. You have to pull the dashboard off to get to it. Has anyone been able to fix it by going in through the removed glove compartment opening and cutting a hole in the plenum? My mechanic thought that might be an option. I'm certainly not going to pull the dash! Some one said its the EATC module. What is that and where is it? Is it inside the firewall or on the engine side? Please advise.

58 of 58 people found this helpful.
380

i had same problem ,in my case the the air would be directed automatically to the defrost vents when im accelerating the car, and would change to the front vents when i lift my foot off the gas pedal and let the car to decelerate. this was quite irritating during normal driving for me .so eventually i checked the vacum line under the dash behind the ac switching control panel (EATC) and found that there was reasonable vacum force present,then i realised that the actuator connected to the vacum line pulling the vent slector door might have gone aged a bit so i pushed the actuator in a position where the air comes from the front and clamped its actuating shaft with a steel clamp so that it never returns back or changes to defrost position , this actuator can be accessed from passenger side to the left and below the glovebox

38 of 38 people found this helpful.
210

my 2006 grand marquies is blowing hot air it was working untill i got motor blower replaced thank you

18 of 18 people found this helpful.
40

My '05 MGM is doing the same thing. Attempted to get it fixed - Tried new temp controller, not the fix. Mechanic says there may be a short somewhere that is affecting the temp controller (manual system, not automatic).

4 of 4 people found this helpful.
200

I'm having this issue now! It's blowing cold air but will switch from floor, vents back and forth all by itself!

20 of 20 people found this helpful.
20

My 03 mgm is blowing cold but only out defrost and floor and a strange thing at highways speeds 45 70 or so only with a/c on will hunt for gears every 20 seconds

My 2008 MGM module is dead and nothing works on selector switch module.

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