Ever since I bought my2006 Ram 1500 Hemi in September, I was wondering if the electric fan always runs when you set the air mixture control on the vent/windshield defrost setting. Does everybody else's truck do the same, or is there something wrong with mine?

Thanks.

 

Well living in Alaska, I usually drive with the defrost on, and ya, ive noticed my fan is on a lot of the time. and it doesnt matter if the truck is warmed up or cold., the fan still goes a lot. So hopefully its normal, cause if not, we both got problems haha oh, btw, my truck is an 02' 1500 5.9L just incase you were wondering

 

When you turn on your defroster the AC automatically comes on. The AC dehumidifies the air thus allowing you to defrost more effectively. This is why the AC fan runs.

 

Thanks for the explanation, I had wondered about that for along time, and that makes sense now.

Withthe AC compressor running in defrost,your mileagewill suffer and it puts wear and tear on the AC system.

 

Thanks for the reply. I've been wondering this since I bought the truck.

 

They also run the a/c in the winter so that oil is kept on the seal in the front of the compressor.