Steve,
I again want to stress that my experience was with an 83 W126 and not the 85 W123. With the 83, a non functioning A/C Freon system would have no effect what so ever on the vacuum actuators. The same thing is true on my 86 SDL. The push button control unit controls both but that is their only link. The control unit sends signals to the 6 or 7 (on the 83 it is 6 yours may be 7, my SDL has 7) vacuum valve header block. I first tested each of the actuators by disconnecting the line to the block and then using a mightyvac to test each actuator. I then tested each of the valves by separately running through all of the climate control cycles with a vacuum gage hooked up to each - one at a time. If you do not get vacuum when you think you should them it is either a faulty valve or the control unit. I have yet to hear of a faulty valve so my first assumption was the control unit. It turned out that for the 83 the ACC unit was bad. I also replaced most of the vacuum actuators as one did have a rip and I figured the others soon would. This is not the easiest or most fun job around since it involves electroincs. Anytime you lack a detailed troublshooting manual, it's mostly guess work until you get some experience with it. Good luck!

__________________
D. Blake
86 300SDL 340K (for sale)
83 300SD 205K (gone)
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