Originally Posted by Budman1962
Sorry for not being specific. It would switch on about every minute or minute and a half. And it would only stay on for about that much time. It seemed odd I thought it only was supposed to come on in the ac or defrost mode. It does this in the combination modes but not in the floor mode.
I think it's fine. Mine does that too. I don't think the compressor even turns on in the floor mode. Only A/C and defrost. See, in order for the air to "defrost" the windshield, it has to have a low humidity. When you turn the controls to "defrost" it activates the compressor, which dries the air out, and then blows it onto the windshield in an effort to defog the windshield. Even in a combonation mode, the compressor is still running. It's a way of keeping the relative humidity of the truck down and preventing condensation.
I always leave my controls set on A/C max. Even in the winter. I just turn up the heat a little bit.
When your truck is in "max" it draws air from inside the cab instead of from outside. It helps keep dust, smoke, dead animal smell, etc.. out, and it keeps all my windows from fogging up by keeping the humidity low.