Initial Inspection and Diagnostic Overview

TROUBLE DIAGNOSIS PROCEDURE FOR A/C SYSTEM

A/C System (Main Power Supply and Ground Circuit Check) - Inspection Flow:

SYMPTOM:
* A/C system does not come on.


MAIN POWER SUPPLY AND GROUND CIRCUIT CHECK
Component Descriptions






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 display (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 Display (and NAVI) control unit. 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.

Diagnostic Procedure / Nos. 1 - 2:

DIAGNOSTIC PROCEDURE

SYMPTOM:
* A/C system does not come on.