HVAC vent control switch


Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,740
Largo, Florida
The rotary knob controlling the vents started acting up within the last several years and wouldn’t activate the defroster. Now it won’t activate any vent other than the dash vents. What’s the latest news on repair or replacement?
 

twobjshelbys

GT Owner
Jul 26, 2010
5,492
Las Vegas, NV
The rotary knob controlling the vents started acting up within the last several years and wouldn’t activate the defroster. Now it won’t activate any vent other than the dash vents. What’s the latest news on repair or replacement?
First, isn't this a known issue that involves the diverter baffle??? Are you sure that isn't what you're seeing?

If it isn't... I had my control board out when I changed the short throw shifter back to stock. I have some memory of the board. I think you have two choices. Both involve removing the board.

1. Pull it and see if there is a vendor part number on the control. I don't know what kind of control it is. But for this kind of control Ford isn't going to engineer something unique. If you can see a part number then check Digikey as they have most electronic parts like that. Then you'll have to desolder and replace it. There are some electronic repair places that will do this kind of work. (I had a cooperative person in our board shop.)

2. If that fails, replace the board...
 
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Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,740
Largo, Florida
Thank you. This car has been so trouble free over thousands of miles and 15 years of ownership that I’m surprised when something does break.
 

fjpikul

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Jan 4, 2006
10,709
Belleville, IL
I think there is a set screw on the knob. Easy fix, BUT regardless you will have to pull the console to see. You might find it in a parts diagram, but it may be easiest to call Rich and find out. What do you need a defroster for in Florida?
 
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GT101

*UK Support*
Supporting Vendor
Jan 20, 2010
322
Colchester, Essex, UK
We've not seen a control actually fail - much more common is the motors that move the blend doors - there are three and they are deeply buried in behind the cross car beam which means access is a major task.
The heater box that they're mounted on is one of the first parts put into the body during build so you have to remove a ton of stuff to get to them. Motors themselves are not expensive.
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,740
Largo, Florida
We've not seen a control actually fail - much more common is the motors that move the blend doors - there are three and they are deeply buried in behind the cross car beam which means access is a major task.
The heater box that they're mounted on is one of the first parts put into the body during build so you have to remove a ton of stuff to get to them. Motors themselves are not expensive.
Thanks. I hope that isn’t the problem.
 

twobjshelbys

GT Owner
Jul 26, 2010
5,492
Las Vegas, NV
What I mentioned as baffles == blend doors. Based on history it's most likely the problem. I'm surprised noone has managed come up with a means to snake a camera prob to confirm with disassembling the dash.
 

GT101

*UK Support*
Supporting Vendor
Jan 20, 2010
322
Colchester, Essex, UK
What I mentioned as baffles == blend doors. Based on history it's most likely the problem. I'm surprised noone has managed come up with a means to snake a camera prob to confirm with disassembling the dash.
We do use a camera probe to check the fault here - unfortunately that's the easy bit..
 

GT Tech

Ford GT Team Alumni
Aug 13, 2006
537
Kingman, Arizona
I have someone down here (a former GT owner) who handles the sticky blend door issue. He has done several for me and has only ran into one car the will require HVAC assembly removal. Just a reminder, every time you drive your 05/06 GT, take a few seconds to run the HVAC blend controls through a cycle. (floor to defrost) Especially important in our beautiful western / southern heat.
 
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Tomcat

GT Owner
May 23, 2013
1,001
North Carolina & Perdido Key
I have someone down here (a former GT owner) who handles the sticky blend door issue. He has done several for me and has only ran into one car the will require HVAC assembly removal. Just a reminder, every time you drive your 05/06 GT, take a few seconds to run the HVAC blend controls through a cycle. (floor to defrost) Especially important in our beautiful western / southern heat.
I'd like to talk with him about any "secrets" or a path to trouble-shoot/fix an in-op/sticking mix door.
 

GSix

GT Owner
Aug 27, 2021
6
Chicagoland
Thanks for the tip on cycling the blend controls. Newbie here and it's great to pick up on the anecdotal knowledge.