Rear Window Defroster Problems

Defroster grid repair kit

Rear window defroster problems can cause poor visibility through the rear glass and on some models the side view mirrors are connected to the same system. This article covers a few of the common problems with electrically operated defroster systems as well as a few facts about how it operates.

Whether you call it a window defroster, deicer or defogger what were all talking about is heating the rear glass to remove moisture particles that can collect on the glass and reduce visibility. The major components of the rear window defroster on most models will include a manually operated on off switch, one or two relays and the heating elements on the glass surface.

The front windshield uses forced air that has had the moisture removed from it by the air conditioning evaporator to dry the front and side windows with warm low humidity air. This is a more efficient method than the heated grid that is commonly mounted on the rear window glass. Therefore slower defogging should be expected. Read more