Electrical Troubleshooting Guide; Reset Or Power Check - LG BD370 Service Manual

ELECTRICAL TROUBLESHOOTING GUIDE

1. RESET OR POwER CHECK

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
Lpb801+5V, pin4 of Lpb801+12V
respectively after the power
cable connecting?
<power>
Is the pin2 of LIC901
<power>
Is the pin2 of LIC903
does the pin120
(Reset in) of LIC501 change
0V to 1.63V at the power supply
initial input mode?
Are the LX501 oscillating?
<Reference>
1.65V (V14ref) :
Check pin1 of LIC501
2.2V (VFVREF) : Check pin2 of
LIC501 2.2V (VhAVC) :
Check pin3 of
LIC501
LGE Internal Use Only
YES
YES
3.3V?
YES
1.2V?
YES
YES
YES
YES
Ok
NO
Check the power (5V/12V) signal
path from smps.
Repair the smps block
NO
Check the LIC901 and
LIC901 input voltage 5V (pin#3)
NO
Check the LIC902 and
LIC902 input voltage 3.3V (pin#3)
NO Check the AVCC 5volt and
Reset Circuit.
(LR5b0,LR5b1,LC5b0)
NO
Check the LX501(25mhz),
Check the LIC501
NO
Check the LIC501
4-2
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