LG Electronics LA120HPO, LA090HPO, LA120CPO, LA120HPI Compressor/Outdoor Fan are unable to drive

Troubleshooting Guide

Compressor/Outdoor Fan are unable to drive.

Turn on Main Power

Operate "Cooling Mode( )" by setting the desired temperature of the 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), R04H(6.2K), Micom (No.27) (Indoor unit).

• Check the indoor temperature sensor is disconnected or not(About 10kΩ / 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 AC200V) 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).

Check point	COMP ON	COMP OFF
Between Micom(No.	DC5V	DC0V
5, 6) and GND
Between IC01M, IC02M(No. 9)	Below DC 1V	About DC12V
and IC01M, IC02M(No. 8)	(app)

Turn off Main Power

•Check the electrical wiring diagram of outdoor side.

•Check the abnormal condition for the component of Compressor/Outdoor Fan Motor.

Service Manual 65