Electrical Troubleshooting Guide - LG RCT689H Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

Reset or power check.
Check it after connecting the power cable
only on interface cable for NO Reset or
Power ON.
Are the pin1 of
LPB272+5V, pin4 of LPB272+12V
respectively after the power cable
connecting?
YES
Does the pin1
(Reset) of LIC401 change 0V to 3.3V
at the power supply initial input
mode?
YES
Are the LX201 oscillating?
YES
<Power>
Is the pin2 of LIC701
3.3V?
YES
<Reference>
1. 65V (VHALF) :
Check pin116 of LIC101
2. 2V (HDVREF) :
Check pin80 of
LIC101
YES
OK
NO Check the power (5V/12V) short.
Repair the SMPS Block
NO
Check the LIC401.
Check the LX201 (16.9MHz).
NO
Check the LIC201.
NO
Check the LIC701.
NO
Check the LIC101.
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