LG Flatron L1750SQ-SNN.AN QP Series - Troubleshooting Guide

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TROUBLESHOOTING GUIDE
1. NO POWER
NO POWER
(POWER INDICATOR OFF)
CHECK KEY CONTROL
CONNECTOR ROUTINE
CHECK U201
NO
NO
NO
CHECK POWER BOARD,
AND FIND OUT A SHORT
POINT AS OPENING
EACH POWER LINE
CHECK 5VS LINE
(OPEN CHECK)
CHECK 3.3V LINE
NO
CHECK X-TAL
YES
YES
YES
YES
CHECK J705
VOLTAGE
PIN5, PIN6 (5V)?
CHECK
U501 PIN 8 Voltage
(5V) ?
IS U201
PIN90 (3.3V)
VOLTAGE ?
CHECK U201 PIN 96
PULSE
1
NO PROBLEM
1
Waveforms
U201-#96