Operational Test

Place a thermometer in the center vent and a second in the engine compartment. Set heater fan at Speed II and the A/C switch to ``recirculated air''. With an ambient air temperature of approximately 64-75° F, the temperature of the air leaving the center vents should be approximately 43° F after 3-5 minutes.
The level of refrigerant in the A/C system must be checked at the sight glass every year at the start of the summer, if possible, or every 12,000 miles. Always check for leaks using leak testing equipment.
The condition of refrigerant hoses and hose clips must also be checked, especially for chafing. The system should be topped off after about two years.
Check for blown fuses, loose wire connections, damaged wiring or collapsed hoses. Inspect for loose defroster ducts and air leaks in the body.