I have a 2005 merc gran marquis. No matter what I select on the temp control I get hot air out of the defroster. Always get hot air even when I have the temp control to off. The blower control works
I take it you have the Automatic Tempature Control Unit (ATC) it needs rebuilding there are all kinds of companies that do it online for around $100.00 but if you are mechanically inclined there is a guy online that shows how to do it for about $5.00 in parts. Sorry can't remember the guys website try searching Ford ATC problems and you might find it that way that was the way I found him. From about 2000 on these units were noted for doing this and of the older ones (which are better) aren't interchangesble!!
Thank you for the info
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