heater controls stuck on defrost

[Dave.O]

99 cobra
while removing stock mach stereo to install gauges I had to move AC/heater control panel.
while reinstalling heater panel I noticed that the yellow vacuum line was disconnected.
Where does it go?
heat mix and fan speed nobs appear to work normally (elec Connections), but vent control is stuck on defrost.
searching on google turned up diagrams from fox bodies where this line connects to a vacuum diaphragm but I cannot find this on a new edge body style

thanks

 

[52merc]

The yellow vacuum line controls the vacuum motor that operates the flapper that directs air flow from the defroster to the floor/console vents, but you already know that. The line goes from the selector switch to the motor. On the back of the selector switch there is a little vacuum manifold that is held in place by 2 nuts. The line probably pulled out from there.

If it came off the motor side it attached as shown (1) below.

Sorry for the poor pictures. They are from the Ford electronic shop manual.

 

[Dave.O]

thanks for response, this is what I needed.
It did not come off selector switch it came off the motor.
where is the motor located?

 

[52merc]

I'd have to open up the dash to find out. The shop manual doesn't give you any locations for the vacuum stuff, just all the electronic parts. I'd start looking behind the glove-box. The glove-box is pretty easy to open up and get behind. I've had my dash apart when I replaced all the Mach 460 stuff, but I wasn't looking for vacuum motors, so I can't be a lot of help.

 

[Dave.O]

Found it. Straight behind radio controls behind metal supports. Had popped off bottom port.
Thanks for the help


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[98 svt]

Found it. Straight behind radio controls behind metal supports. Had popped off bottom port.
Thanks for the help


Sent from my iPhone using svtperformance.com

Thanks for updating the thread for others in the future.

 

[03cobra#694]

Thanks for updating the thread for others in the future.

Exactly. Good job guys.

 

[52merc]

Behind the radio was going to be my second guess. It would just have been a lot easier if it had been behind the glove-box.

 

[shurur]

There is vacuum feed hose coming in through the firewall.

There is a default HVAC setting the system gets stuck in when this line is leaking or broken. I forget what that default is,,but vaguely remember it being stuck-on-defrost....

So that is another place to look.
It is another common problem.