2003 Chevrolet Monte Carlo Owner's Manual - Page 139

If your vehicle has heated outside rearview mirrors, the mirrors will heat to help clear fog or frost from the surface of the mirror when the rear window defog button is pressed. Notice: Don't use anything sharp on the inside of the rear window. If you do, you could cut or damage the warming grid, and the repairs wouldn't be covered by your warranty. Do not attach a temporary vehicle license, tape, a decal or anything similar to the defogger grid. Operation Tips Clear away any ice, snow or leaves from the air inlets at the base of the windshield that may block the flow of air into your vehicle. Use of non-GM approved hood deflectors may adversely affect the performance of the system. Keep the path under the front seats clear of objects to help circulate the air inside your vehicle more effectively. 0 Outlet Adjustment Use the knob located below or to the side of the outlet, to change the direction of the air flow. If the airflow seems low when the fan is at the highest setting, the passenger compartment air filter, if equipped, may need to replaced. For more information, see Passenger Compartment Air Filter on page 3-25 and Part A: Scheduled Maintenance Services on page 6-4. 3-24