Compressor/Outdoor Fan Are Unable To Drive - LG LA121HPMI Service Manual

Troubleshooting Guide

Compressor/Outdoor Fan are unable to drive.

Operate "Cooling Mode(
remote controller is less than one of the indoor temperature by 2°F at least.
When in Fan Mode, Compressor/Outdoor Fan is stopped.
Check the sensor for indoor temperature is attached as close as to be
effected by the temperature of Heat Exchanger(EVA).
When the sensor circuit for indoor temperature and connector are in bad
connection or are not engaged, Compressor/Outdoor Fan is stopped.
• Check the related circuit of R02H(12.1K), R01H(6.2K), Micom (No.46, 47)
(Indoor unit).
• Check the indoor temperature sensor is disconnected or not(About 10k / at 77°F).
When the temperature around Outdoor PWB Ass'y is above 163°F the
compressor is stop and only Outdoor Fan is operating.
Check Relay(RY - COMP) for driving compressor.
• When the power(About AC110V) is applied to the connecting wire termi-
nal support transferred to compressor, PWB Ass'y is normal.
• Check the circuit related to the relay(Outdoor unit).
Between IC01M, IC02M(No. 9)
• Check the electrical wiring diagram of outdoor side.
• Check the abnormal condition for the component of Compressor/Outdoor
Fan Motor.
52 Room Air Conditioner
Turn on Main Power
)" by setting the desired temperature of the
Check point
Between Micom(No.
5) and GND
and IC01M, IC02M(No. 8)
Turn off Main Power
COMP ON COMP OFF
DC5V DC0V
Below DC 1V
About DC12V
(app)