vacuum servo/actuator mk3

[fred27]

Hi All,
the fresh air/recirculate flap that is worked by a vacuum servo/actuator is stuck in fresh air position. The button lights up
(slight humming sound) but the flap does not move. I checked all the hard plastic lines and there are no breaks. I'm not
sure about the layout under the dash and would like to ask first before poking around with an airbag near by.
Appreciate any fixes/replacement advice.
Thanks

[mattross]

Ahhhh, common problem that.
Behind the Coolant Bubble on the firewall is a small solenoid valve. Check that and trace the hose to the heater core where it connects thru the firewall, it may have come off.
Otherwise disconnect the vacuum hoses and blow them all clean. If its the solenoid you can disconnect and test with 12v. otherwise it way be your cabin switch button
While your in there, check to see if you have a blockage under your cabin filter.

[fred27]

Appreciate your quick response and advice. Thank you, will follow your directions.

[fred27]

Thanks very much, the hose to the heater core came off, flap working now.