LG HDR676X - Electrical Troubleshooting Guide

4-2
ELECTRICAL TROUBLESHOOTING GUIDE
Are the pin 44 of
LPB271+5V, pin41 of LPB271+12V
respectively after the power cable
connecting?
Reset or Power Check.
Check the power(5V/12V) short.
Repair the SMPS Block
Check the LIC401(3.3V regulator IC).
Check the LIC201, LIC121.
Does the pin #1
(Reset) of LIC271 change 0V to 3.3V
at the power supply initial input
mode?
<Power>
Is the pin 5 of LIC401 3.3V?
<Reference>
1.65V(VREF) : Check pin113 of LIC121?
2.2V(HDVREF): Check pin78 of LIC121
NO
NO
YES
YES
YES
YES
Are the LX201 oscillating?
Check the LX201(16.9MHz).
Check the LIC201.
NO
Check the LIC401.
NO
Check the LIC121.
NO
Check it after connecting the power cable
only on interface cable for NO Reset or
Power ON.
YES
OK