Does anyone know if the Green AC light should be lit when the air control is set so air is directed to the windshield (defrost) even when the AC button(switch) is not pushed to turn on the AC. I also have a 1998 Montero Sport and when the air control is set to defrost in winter the Green AC light is lit. If the Green AC light is not lit on the 2004 does this mean the Heater control panel/SW is defective. The Green AC light does come on when the button is pushed for AC.

 

On the 98 model Montero Sport- the light came on automatically when the position was switched to any of the defrost modes. The AC came on automatically in these modes to help remove moisture from within the cabin. In later models- the light did NOT come on when in defrost- BUT the AC still switched on to aid in defrosting. Many customers of the earlier models complained about not being able to switch off the AC when in defrost- so Mitsu decided not to illuminate the lamp thereafter.

JJ