Off

When the driver selects the OFF mode, the blower motor will operate at the motor's minimum calibrated speed. The A/C compressor will turn OFF.

The heater and A/C programmer will allow all of the vacuum actuators to vent. The valves are positioned in the following manner:
^ The air inlet valve is in the outside air position.
^ The heater-A/C bi-level valve vacuum actuator is in the bi-level position.
^ The defrost-A/C valve vacuum actuator is in the defrost position.

When the vehicle is moving, air flowing over the vehicle increases the air pressure just ahead of the windshield. This forces some of the air through the following path:
^ Into the outside air inlet
^ Through the heater and A/C module assembly
^ Out of the floor outlet and the windshield outlets

The temperature control circuitry is still activated, so the heater and A/C programmer operates the air mix valve. The programmer attempts to match the inside temperature set by the occupant of the vehicle. Because the compressor is not running, the system air may be warmed, but the air cannot be cooled.