88 2M4 w/AC

I just replaced my HVAC control unit. Was working fine but 2 of the button [covers] popped off, lost one.

When you turn the A/C on, the cooling fan comes on which is normal. When you turn on the defrosters, the A/C compressor kicks on which again is also normal. I can't remember if the cooling fan is supposed to come on as well during this [defrost] cycle. Reason asking, because mine doesn't.

defog=ac-on,rad fan-off
Too cold... Low pressure limit switch cuts power to AC

------------------
Dr. Ian Malcolm: Yeah, but your scientists were so preoccupied with whether or not they could, they didn't stop to think if they should.
(Jurassic Park)

The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)

Sorry, I tend to get too wordy or try to over explain.

Turn defrosters on, A/C compressor kicks on, defrosters work. Question was: Is the [radiator] cooling fan supposed to come on in the defroster mode?

Thanx again

No sir. The radiator fan is NOT suppose to turn on in defrost mode. Only Max, Norm, and Bi-level should turn on the radiator fan.