Electronic Parts Troubleshooting Guide - LG TN-C090BT00 Service Manual

Electronic parts Troubleshooting Guide

Possible trouble 1
Is the input voltage of
transformer AC220V?
YES
Is the output voltage of
transformer AC24V & AC13V?
YES
Is the output voltage
of IC02D(7805) on the
main PCB DC5V?
YES
Is the output voltage
of IC01D(7812 ) on the
main PCB DC12V?
YES
Is the output voltage
of IC01A(7036) on the
main PCB DC5V?
YES
OSC vibration?
YES
1. Exchange main PCB ASS'Y
Possible trouble 2
Is the power ON?
YES
Is the input voltage
of remote-controller
DC12V?
YES
1. Exchange remote-controller
2. Check or exchange the Main
PCB ASS'Y.
: The unit does not operate.
NO
NO
NO
NO
NO
NO
: The remote-controller does not operate.
NO
NO
19
1. Check the Fuse.
2. Check the wiring of AC220V.
1. Exchange the transformer.
2. Check the connector of
transformer.
1. Exchange IC02D(7805) on
the main PCB.
2. Check the D01D~D05D, R05C
on the main PCB.
1. Exchange IC01D(7812) on
the main PCB.
2. Check the D01D~D05D,
R05C on the main PCB.
1. Exchange IC01A(7036) on
the main PCB.
1. Exchange OSC.
2. Check the pattern around
OSC on the main PCB.
1. Exchange or exchange FUSE.
2. Check the input voltage of
Main PCB ASS'Y.
1. Check or exchange the IC01D
on the Main PCB.
2. Check or exchange the
Connector (RED, BROWN)
of the remote controller.