Introduction

The Automatic Temperature Control ATC system provides automatic regulation of the vehicles interior temperature. This system is based on the operator selected set temperature, regardless of the outside temperature changes. This is done by utilizing a microcomputer, also referred to as the automatic amplifier, which receives input signals from several sensors. The automatic amplifier uses these input signals (including the set temperature) to automatically control:
^ Outlet air volume
^ Air temperature
^ Air distribution

Features
^ Air mix door control (Automatic temperature control)
The air mix door is automatically controlled so that in-vehicle temperature is maintained at a predetermined value by: The temperature setting, ambient temperature, in-vehicle temperature, amount of sunload.

^ Fan speed control
Blower speed is automatically controlled based on temperature setting, ambient temperature, in-vehicle temperature, amount of sunload and air mix door position.
With FAN switch set to AUTO, the blower motor starts to gradually increase air flow volume.
When engine coolant temperature is low, the blower motor operation is delayed to prevent cool air from flowing.

^ Intake door control
The intake doors are automatically controlled by: The temperature setting, ambient temperature, in-vehicle temperature, amount of sunload and ON-OFF operation of the A/C switch.

^ Outlet door control
The outlet door is automatically controlled by: The temperature setting, ambient temperature, in-vehicle temperature, and amount of sunload.

^ Self-diagnostic system
The self-diagnostic system is built into the auto amplifier to quickly locate the cause of problems.