Today I was able to perform the some of the simple ACC test that are outlined in the ACC manual. This is what I found:
Total Vent Cooling works when switching from defrost, otherwise no,
Ventilation blower works,
The vents are regulated by the temperature wheel as expected,
Econ-mode fails to disengage compressor,
Compressor does disengage when I ground the tempreture sensor coolant,
After about an hour on the road the whole system (all vents) closes up and the compressor continues to run. On a long trip it has been known to come back to life after another hour. It also returns to life after sitting for about twenty minutes.
Based on this I plan to replace the button control unit in the console. If anyone things I'm miss guided please let me know.
'87 300TD Turbo