Checking The Dc/Dc Converter Circuit - NEC MultiSync LCD1525V Service Manual

11. Checking the DC/DC converter circuit

Check if the 5V is output from I102 pin 2.
NG
OK
OK
OK
OK
Check the output of 3.3V line voltage from I103 pin 2.
NG
OK
OK
Printed wire broke between I103 pin 2 and IC 401 power supply pin.
Check if TTL "H" is output from Q102-base.
NG
Q101, D101, R101, R102 circuit.
Check if the 12V is output from I101 pin 5,6,7,8.
NG
I101 failure.
Check the input of 12V to the I102 pin1.
a
Is the output FB108 being inputted to I103 pin 3?
NG
Printed wire broke between I103 pin 3 and output of FB108.
Failure point
I103 failure
Failure point
Failure point
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