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Control Module HVAC: Description and Operation

Power Supply and Ground Circuit for Auto Amp.

COMPONENT DESCRIPTION




Automatic Amplifier (Auto Amp.)
The auto amplifier has a built-in microcomputer which processes information sent from various sensors needed for air conditioner operation. The air mix door motor, mode door motor, intake door motor, blower motor and compressor are then controlled. The auto amplifier is unitized with control mechanisms. When the various switches and temperature adjustment dial are operated, data is input to the auto amp. from the AV control unit or AV and NAVI control unit using multiplex communication.

Self-diagnostic functions are also built into auto amplifier to provide quick check of malfunctions in the auto air conditioner system.




Potentio Temperature Control (PTC)
The PTC is built into the multifunction switch. It can be set at an interval of 0.5 °C (1.0 °F) in the 18 °C (60 °F) to 32 °C (90 °F) temperature range by turning the temperature dial. The set temperature is displayed.