Just starting to have ac issue with my vintage air, when I put ac on (far right knob) the blue light does not come on anymore ? I hear the compressor engaging and the motor idling down when I turn the knob to ac but no blue light or ac? also could have sworn the blue light came on even when car was not running with just keyed power? Can someone check there unit to see if there blue ac light comes on with just keyed power….it will help me trouble shoot….or any other ideas you would have would be great..thanks