I OWN A 2003 JEEP GRAND CHEROKEE LIMITED WITH 90,000. THE EVENTS LEADING UP TO THE FAILURE OF THE VENTILATION SYSTEM WERE (1) RAPID FOGGING OF FRONT WINDSHEILD,(2) FOGGING OF FRONT PASSENGER WINDOWS,(3) FAILURE OF PASSENGER HEAT WHILE STILL MAINTAINING DRIVER HEAT FUNCTION, AND (4) ONLY COLD AIR RELEASE ON PASSENGER SIDE OF JEEP. CONSEQUENTLY,(1) THE WINDSHEILD AND FRONT WINDOWS DO NOT DEFOG, AND (2) NO HEAT WHATSOEVER COMES FROM THE PASSENGER SIDE FLOOR AND DASHBOARD VENTILATION SYSTEM. TO CORRECT THIS PROBLEM, A "BLEND AIR DOOR" IS NECESSARY AT A COST OF APPROXIMATELY $1,200 INCLUSIVE OF 7 HOURS OF LABOR. ACCORDING TO THE CERTIFIED SERVICE DEPARTMENT AT THE LOCAL JEEP DEALER AND ONLINE FORUMS, THIS HAS BECOME A VERY COMMON PROBLEM FOR 2000-2004 JEEP GRAND CHEROKEE LIMITEDS WITH DUEL ZONE VENTILATION SYSTEMS. *NM