Front AC/Heat control issue

[johndrop]

Hi I am new here but I have learned alot and fixed several problems. Currently I have a 2004 Expedition Eddie Bauer 5.4 and the heat/ac works but doesn't switch from defrost to dash to floor. It seems stuck on defrost. Any suggestions? Has this been discussed because I haven't been able to find it. I found one that suggest its the damper door gearbox broken. I am going to head in that direction if I don't hear a better simpler suggestion.

Thanks in advance

 

[GAINMOB]

Blend door is stuck or inoperable due to bad motor I believe

Holy Rollerz Christian Car Club (HRC3)

 

[Hamfisted]

Check the vacuum line located between the battery and firewall also (no, it doesn't connect to the battery, that's just the general location...). The supply vacuum line is notorious for cracking and causing a loss of vacuum to the controller. The default position for the blend door is the defrost mode.



-Mike

 

[johndrop]

Thanks will check vacuum hose first as that is easier.

Where can i get the vacuum hose if that is the problem? NAPA or other auto supply stores?

 

[bedrck46]

Condition
Incorrect/erratic direction of airflow from outlet — DATC

Possible Sources
DATC module.
ATC solenoid and manifold assembly.
Vacuum hose.
A/C vacuum reservoir tank and check valve.
Vacuum control motor.
Vacuum actuator arm.
Mode door.