LG Flatron L1753 - Troubleshooting Guide; No Power Troubleshooting

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TROUBLESHOOTING GUIDE
1. NO POWER
NO POWER
(POWER INDICATOR OFF)
NO
CHECK POWER BOARD,
AND FIND OUT A SHORT
POINT AS OPENING
EACH POWER LINE
NO PROBLEM
1
Waveforms
U101-#96
CHECK KEY CONTROL
CONNECTOR ROUTINE
CHECK U501
NO
NO
CHECK 3.3V LINE
(OPEN CHECK)
CHECK 3.3V LINE
NO
CHECK X-TAL
YES
CHECK J905
VOLTAGE
PIN5, PIN6 (5V)?
CHECK
U901 PIN 2 VOLTAGE
(3.3V) ?
IS U501
PIN87 (3.3V)
VOLTAGE ?
CHECK U501 PIN 127
PULSE
1
YES
YES
YES