'94 E420 A/C Erratic Behavior
 

The first $$$Costly behavior!

In hot summer weather, typical of Southern Oregon, the A/C will not function. I try to go to all buttons on the console as well as move the temp.wheel to and fro. The a/c will not kick in.
After car has been turned off and restarted the a/c will work if the a/c buttons have been selected and the temp.wheel is in 65° or less setting.

To fix our dealer took $750 to replace several switches and filters etc.!

The problem is not solved if I switch from a/c to economy or off with engine running. Sometimes a/c is not needed even here!
It was suggested that I allow more time after switching back and forth.
It was suggested that I not switch at all when it is working?

Any thoughts would be appreciated.
Answers please?

More information
 

Please let us know exactly what the dealer replaced. This sounds to me like a bad circuit board in the A/C control unit, but I want to make sure that the dealer didn't already replace befor eoffering suggestions.

Troy
1995 E420
83k

OK, here is the parts replaced list:

140-830-04-84 Expansion Valve
124-830-03-83 Container
004-820-68-10 Switch, Liqui
124-820-83-10 Switch, Recei
140-997-09*-45 Seal Ring, VL in OR (3 additional seal rings: (*08-07-06)
124-830-01-18 Air Filter

That parts list amounts to $296.00

Tech(s): 123 171

Any thoughts?