Heating and Air Conditioning: Description and Operation

The heater system uses a two-way-flow full-air-mix system that features high performance and low operating noise, and includes an independent face air blowing function and a cool air bypass function.
The A/C system is basically the same as the conventional system, but a new
refrigerant system has been adopted as a response to restrictions on the use of chlorofluorocarbons.

OPERATION
Condenser fan and radiator fan control
- For the operation of each fan, refer to COOLING SYSTEM TROUBLESHOOTING.

Compressor control
- When the air conditioning switch is pushed in (A/C switch: ON) or the air outlet changeover control knob is moved to the DEF or DEF/FOOT position (defroster switch: ON), the air conditioning system operates and compressor control starts.
- The fin thermo sensor, which senses the temperature of the air flowing out of the evaporator, is deactivated with temperature 3.2 °C (38 °F) or below.
Here, the engine coolant temperature sensor senses the temperature of engine coolant, and it is turned OFF at 115 °C (239 °F) or higher temperatures.
- The dual pressure switch turns OFF when the refrigerant pressure becomes excessively high or low, thus protecting the compressor circuit. (See Table .)




A/C Compressor Relay ON Conditions