NEC NEC MultiSync LCD1525V LCD1525V LCD1525V, Service Manual

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9. Checking the resolution change IC movement
Is there +3.3V supply on I401 pin A19, B20, C2, D6, D8, D10, D11, D12, D19, D20, F3, F4, G17, H3,
J3, J4, K4, K17, L17, M17, N4, N17, P4, U6, U8, U9, U11, U13, U14 and V17
OK
NG
Proceed "Checking the DC/DC converter circuit" section.
Is 50MHz clock input to I401 pin D1 at TTL level?
OK
NG
Is 50MHz clock output from X401 pin 5 at TTL level?
OK
NG
Is +3.3V supplied to X401 pin 8?
Failure point
Print wire broke between X401
pin 5 and I401 pin D1.
OK
NG
Failure point
Print wire broke between X401
pin 8 and power supply.
Failure point
X401 failure.
Is +5.0V supplied to I401 pin A12 at
High level?
OK
NG
Check the output of 5.0V "H" pulse from I207 pin 1.
OK
NG
Is 5.0V supplied to I207 pin 2?
Failure point
Print wire broke between
I207 pin 1 and I401 pin A12.
OK
NG
Failure point
1) I102 failure
2) L102 open
Failure point
I207 failure.
Failure point
I401 failure.