Troubleshooting Guide - LG Flatron L1930SQ Service Manual

(POWER INDICATOR OFF)
CHECK J705 VOLTAGE
1
PIN5, PIN6 (5V)?
1
U501 PIN 8 Voltage
CHECK KEY CONTROL
CONNECTOR ROUTINE
PIN114 (3.3V)
VOLTAGE ?
CHECK U201 PIN 122
2
CHECK U201
Waveforms
1
J705-#5, 6 / U501-#8

TROUBLESHOOTING GUIDE

NO POWER
YES
CHECK
(5V) ?
YES
YES
IS U201
YES
PULSE
YES
2
U201-#122
1. NO POWER
NO
NO
NO
NO
- 16 -
CHECK POWER BOARD, AND
FIND OUT A SHORT POINT
AS OPENING
EACH POWER LINE
CHECK 5VS LINE
(OPEN CHECK)
NO PROBLEM
CHECK 3.3V LINE
CHECK X-TAL