I have a 99 Expedition and the a/c does not work only in the summer when its really hot i live in Arizona. The air conditioner control panel turns off then the 4x4 light starts flashing the ABS light turns on and the turn singles don't even work and a weird nose comes were the glove box is. Idk what to do or what's the problem Plz help.

 

Sounds to me like a possible vacuum leak in one of the lines under the dash. Could be somebody got their toes up under the dash area on the passenger side. Since your 4x4 is also vacuum operated, I suspect this is the issue. Vacuum is used to operate the blend door for the various vent outputs and Normal/MAX A/C and so on.

 

I have a 2004 Freestar with auto climate control. Problem: Switches to heat and cooling with little or no relationship tpo existing cabin temperature. Replaced actuator doors, control panel and wiring harness. Still does it. Dealer is bafffled. Any thoughts?

 

In regards to your Freestar, When switching, do you mean that it starts putting out heat while say it is still set to A/C and the temperature is set to 60 degrees and then switches back? Does it do this when just setting idling or while driving? If while driving, does it do it while just cruising along, or when you step on the gas to say speed up? A little more information on when the heat/cool change occurs would help. While gathering this info, I would double check all vaccum lines under the dash along with the vaccum line connectors. The blend doors are actuated by vacuum. You may have a bleeding connection (hole/crack) in a vacuum line/connector what is affected by the change in engine vacuum.