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Trouble Diagnosis Procedure For A/C System

TROUBLE DIAGNOSIS PROCEDURE FOR A/C SYSTEM

INSPECTION FLOW:




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


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. Signals from various switches and Potentio Temperature Control (PTC) are directly entered into auto amplifier.

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 A/C auto amp. It can be set at an interval of 0.5°C (1.0° F) in the 18° C (65° F) to 32° C (85° F) temperature range by pushing the temperature button. The set temperature is digitally displayed.

MAIN POWER SUPPLY AND GROUND CIRCUIT CHECK

Power Supply Circuit Check
Check power supply circuit for air conditioner system.
Refer "Wiring Diagram -POWER -".




Step 1:




Step 2:




DIAGNOSTIC PROCEDURE

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