NEC MultiSync LCD1550V Service Manual page 58

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Is 5V-source voltage provided to pins 1 and 2 of J2 in
MAIN board.
NG
OK
Is a dot clock being outputted under the condition that a
LCD module is connected to CN2 and CN3 pin 26?
NG
OK
Check the STH pulse of negative polarity is
output on CN2 pin 29 at TTL level.
NG
OK
Check the STV1 and STV2 of negative
polarity are ouput on CN2 pin 35, 36.
NG
OK
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Is 5V-source voltage provided to pins 1
and 2 of P803 in SW REG board.
OK
Failure point
J2 cable pulled out or disconnected
6-4
NG
Failure point
Error in SW REG board.
Failure point
1) U3 failure.
2) Printed wire broke between
U3 and CN2, CN3 pin26.
3)L10, R63, L11 or R64 failure
Failure point
1) U3 failure.
2) Printed wire broke between
U3 and CN2 pin 29.
3) R68 or L14 failure
Failure point
1) U3 failure.
2) Printed wire broke between
U3 and CN2 pin 35, 36.
3)R72, R73, L18 or R25 failure