Vehicle: '90 Legacy
So my environmental controls aren't broken to their full extent. When the weather is at -20 F my A/C/Vent/Heat/DEF-Heat (NOTE: basic DEF does not work) work without a catch. However, if the tempature gets to around 65 F (give 'er take) the whole ventalation system turns off. Origionally a quick pop to the dash would turn it back on (yeah...i'm quite the engineer). Now it is just temperature dependent and 100 F without A/C is killing me.
I've tried all the combinations of fan speeds to buttons, but all is for not. Any suggestions to the problem or further troubleshooting?