Monaco dash vent and window defrost

[csp]

I have a 95 Monaco Dynasty. The dash does not switch from vent to window defrost. It seems like it stays somewhere between. I can take out the center drawers and manually move it from vent to the window by moving the door linkage. The temperature control works fine but it is run by cable not vacuum. I took apart the dash controller and I could not get any vacuum to any of the lines going to the switches. I looked around at the vacuum lines in the front of the coach but I could not diagnose the problem. Has anyone run in to a problem like this? I could take it to a shop but if it is something I can fix I would rather do it myself.
Thank You for any help.
Chris

[mfire1339]

csp,

I believe you have a vacuum pump forward of dash. Default operation should be defrost= no vacuum though.

Mike

[GOLDWINGER2]

You have a vacuum leak. Double check all rubber/ plastic hoses. Had the prob on mine, took me a while but i found the leak. It was very small.
J

[hardy1000]

I had my vacum pump fail and had to replace it because it started with the same problem that you are describing. After looking for a leaky hose I finally found the pump in the front generator compartment and it was covered with spray foam, (you might have to dig it out like I did to find it). The vacum pump on mine had one of the hose inlet stems broken, so I replaced the pump and it was a ford part and was a warranty part from Monaco so I don't have the cost.

Good luck

[csp]

Thank you for the advice
I will try to find a leak and then check the pump if I can find it. I will post the results.
Chris