heater / AC control problem

I found the previous post that has the calibration test. Get the vehicle to operating temp, fan on high and the temp controls to the far heat position. Press and hold the rear wiper and washer buttons at the same time until all L.E.D's light, this will put the heater control head unit in calibration mode, when done 2 L.E.D's (rear wiper and washer) will flash alternately and then stop when complete.

Thanks I will try this tomorrow

any idea how long this process takes?

It should only take a minute or 2

During the calibration test it will cycle from hot to cold, go through the different fan speeds and through the different levels. It has to pass all the tests for the lights to stop blinking. I have done the test will driving. My 97 ply voy van the A\C is shot and the resistor for the fan speeds is shot too so my lights flash