When the air conditioner is actually blowing it works great. But every once and a while it will just stop working. When I drive about 65 mph and turn it to AC on max a little trickle of air will come out. It will stay like this for an indefinite amount of time and then come back on suddenly. I am not mechanically inclined so I have no clue as to why this is happening.
Either the blower motor is going bad or there is a connector problem. Check the wiring connectors to the controls, to the blower and to the blower motor resistor. When it is not running, try tapping on the blower motor with a short length of timber 2 x 2 or 2 x 4 or a mallet and see if it starts. If it does, and the connection is good, you probably have a motor going bad.
try it with the AC off, with the fan on. if the fan still dies with the AC off, then you have removed the AC as being part of the equation.
with the AC off try the fan on the lowest speed. then work your way up to high speed. any difference?
let everyone know whats happening, you will get more accurate suggestions.
I had a similar problem on the 1990 Ford Aerostar that I once owned. It turned out to be the blower motor. As an earlier post suggested, tap on the blower motor when you aren’t getting air through the dash vents. In my case, I could just open and slam the hood and get the motor to come on.