No heat 1999 deville

I AM GETTING CODES THAT SHOW AIR/MIX DOOR MOVEMENT FAULT DOORS 1AND 2. I KNOW I HAVE TO TEAR APART THE DASH TO LOOK AT THE ACTUATOR ARM OR DOORS THEMSELVES. HAS ANYONE ATTEMPTED THIS B4?CAN ANYONE GIVE ME SOME TIPS AS TO WHAT I AM LOOKING FOR? ANY HELP WOULD BE GREAT. THANKS

Start under the hood and look for a broken or disconnected vacuum line.

Please don’t SHOUT. We can read your message a lot easier if you use proper case.

As for your question, I believe you should start with keith’s suggestion.

Keith I looked under the hood but could not find anything . not really sure what I am looking for? Vacuum lines? u mean rubber hoses? Coming from or attached to where? I did notice one thing there is sort of a black box or covering dead center opposite dash under the hood that reads cut here for service? I used my finger to clean the road dust off to better read it and when I pressed down the plastic just cracked and a small hole was created. I looked inside as best I could see and it looks likes wiring with plastic heat sheilding cables wrapped around them. I dont think this is the problem though. I have read about some real horror stories where one guy paid 800 dollars for the dealer to tear apart the whole dash only to find out what was needed was a 1.00 plastic clip?" Any more help or advice would be great. thanking u in advance.