Contour Enthusiasts Group Archives Forums General Troubleshooting Ventilation always stays in Defrost

My Mystique always stays in the defrost mode no matter where the switch is placed. I've checked the vac pots and they seem ok. Is the positon switch burned out? Help...

This is neat....someone else has this prob. OK....look under your dash on the driver side, middle console. You should see a silver vacuum solenoid (I think this is it's term). It has an arm that moves the internal vents in accordance to what your selector is on ie: max/ac, ac, panel, defrost.

You should be able to see the arm move as you hear vacuum hisses. If you see the bar move out of the solenoid and nothing is attached.....there you are. You will just need to figure out where everything is relately close so that you can pop it back on.

However, if you can turn the selector and you don't hear a hiss, two possibilites. You have not built up vacuum in that solenoid so start the car, move the selector, turn the car off. OR....no vacuum....bad

Hope this helps

Rich

SOSAUDIO is right, The vacuum motor which swings the plenum door to direct airflow has popped of mine since it was new. I removed the Vacuum motor and bent the arm slightly which should have kept it in place better, but it still pops off.

98 SE Sport

From what i know there was a recall for that, i had my done a year ago. Check you dealer for info

OK guys....I got a PM from Terry and he says there is no vacuum going to that actuator when the car is on and everything is connected. The solenoid appears to be working good too. I have a Haynes Manual and it says NOTHING about where the vacuum lines go to or where it comes in.......

Any ideas???? I know how frustrating this is so if you guys can help trace, for him that would be cool

Rich

If the fans stays on high, then it is a burned out fan relay or resistor (I think that is what it's called). That happenned on my SE-R, very easy fix.

vacuum for the HVAC starts in the area around the EGR solenoid, comes off one of the larger pair of black hoses top of manifold. ( has mulitple uses) Goes down along the firewall. Now under the car find the heater hoses center and you will see a single vacuum line. This is the supply to the HVAC.
I've never had mine quit--yet--but this question has come up many times here. Of course the leak or break seems happen in the least accessible area

Lost of vacuum the system deflauts to only defrost.

Paul

Terry
If you have a chance, let us know where the leak or break was? Just trying to see it is a common area or not?
Thanks
Paul

See Terry! You came to the right place. "All for one...and one for all....." Kinda like the "Three Musketeers but with 7000 more!

And to everyone out there that has answered, Thanks for answering!

Hope this helps!

C'mon!!!! Ask CEG another question!!! We are ready for ya!

I had this problem, after pulling the intake for a clean-up. Seems someone had not reattached a small vacuum line near the firewall :rolleyes:

HVAC defaults to defrost in case of insufficient vacuum...might want to check for loose or cracked hoses under the hood...