My B9 Tribeca 2006 Heating system sometimes will not work when I first car.

trinanes

Latley when I start my Tribeca the heating system lights are all on from the last settings when i used the car, but it is not on or working. You cannot make it come on blow air or anything. Even my rear defroster and heated seats won't come on. then five minutes later it all works fine. It has done this about a 1/2 a dozen times the last couple months..Any Ideas?

ttentelh

the engine needs to warm up first before it starts producing hot air. When the engine gets warm then it starts. Also don't forget its a climate a/c system not the old conventional system.