NHTSA Complaint #756776 — 2000 CHEVROLET BLAZER

WHEN THE COMFORT CONTROL SYSTEM MODE KNOB IS TURNED TO THE OFF POSITION, THE FRONT FLOOR OUTLETS DIRECT HOT AIR THROUGH THESE LOWER VENTS. MOVING THE TEMPERATURE KNOB TO BLUE (COLDEST AREA) HAS NO EFFECT. WARM HOT AIR CONTINUES TO VENT WITH SYSTEM IN OFF POSITION. WHILE THE OWNER'S MANUEL ADVISES THAT WHEN MODE KNOB IS IN THE OFF POSITION "SOME OUTSIDE AIR WILL STILL ENTER THE VEHICLE". IT IS VERY HOT AIR NOT OUTSIDE AIR THAT ENTERS THE VEHICLE. THE ONLY WAY TO ISOLATE THE HOT AIR IS TO NEVER SELECT "OFF" ON MODE SWITCH, AND SELECTING EITHER AIR CONDITIONING OR VENT POSITION (SELECTING THE LATTER SHUTS OFF THE HOT AIR FLOOR VENTS BUT THEN INSTRUMENT PANEL VENTS MUST BE INDIVIDUALLY CLOSED TO STOP AIR FLOW . I HAVE HAD MY VEHICLE IN TWICE FOR THIS PROBLEM AND WAS ADVISED "NPF, NO PROBLEM FOUND". I BELIEVE ONE SERVICE MANAGER WAS MOST CORRECT IN ADVISING THAT THIS WAS A DESIGN FAULT BY CHEVROLET. I CONFIRMED THAT THERE ARE QUITE A NUMBER OF BLAZER OWNERS IN WEB SITE AUTO CHAT ROOM THAT ARE FRUSTRATED WITH THIS FLAW. MY MAIN CONCERN IS THAT THE AIR IS SO HOT THAT EVEN WHEN ARTIFICIALLY ISLOTED BY NON-STANDARD VENTILATION CONTROL SELECTIONS, THERE MAY BE DAMAGE UNDER THE PANELS OR TO THE VENTILATION OR ELECTRICAL SYTEMS. *AK