Electronic Climate Control

CLIMATE CONTROL SYSTEM
How the Air Delivery Circuit Works
The Climate Control unit controls the blower controls, air delivery, and A/C compressor controls either automatically or semi-automatically. The control unit receives battery voltage at all times through fuse 13. With the ignition switch in ON (II), battery voltage is supplied through fuse 3. The control unit is grounded at G401.

Fully-automatic Operation
To put the automatic climate control in fully automatic mode, press the AUTO button and set the fan control dial to AUTO, then set the desired temperature by turning the temperature control dial. You will see FULL AUTO in the system's display.

The system automatically selects the proper mix of cooled and/or heated air that will, as quickly as possible, raise or lower the interior temperature from its current level to the set temperature. The system also adjusts the fan speed and changes direction of air delivery.

When you set the temperature to its lower limit (60° F/18° C) or its upper limit (90° F/32° C), the system runs at full cooling or heating only. It does not regulate the interior temperature. When the temperature is set between the lower and upper limits, the system regulates the interior temperature to the set value.

Semi-automatic Operation
You can manually select various functions of the climate control system when it is in FULL AUTO. All other features remain automatically controlled. Making a manual selection causes the word FULL to go off.

However, when you select A/C OFF, the system cannot regulate the inside temperature if you set the dial lower than the temperature outside.

Air Delivery
The climate control unit controls the blower motor and supplies a 5 VDC reference voltage to the air mixture control motor.

The air mix and mode control motors each receive inputs from the control unit. The air mix motor regulates the mixture of cold and hot air by varying the position of the heater-evaporator door. The mode control motor controls the direction and volume of outlet air. Use the MODE button to select the vents the air flows from. Some air will flow from the dashboard corner vents in all modes. Each time you press the MODE button, the display shows the mode selected. Press the button four times to see all the modes. Both the air mix control motor and mode control motor are grounded by the control unit.

The recirculation control motor receives battery voltage through fuse 3 when the ignition switch is ON (II). It regulates the position of the fresh/recirc door, and is controlled by two position inputs from the control unit ("Recirc" and "Fresh").