Power Is Not Available - NEC MultiSync LCD2080UX -BKA Service Manual

1. POWER is Not Available

Is the vacation switch turned on ON?
Confirm if there is any disconnection of internal cables, disconnections, etc.
Is 5.5V available at CN261 pin 12?
NO
YES
Is 4.2V available at Pin 3 of FL2M1?
NO
YES
Is 12V available at CN2E1 pin 8?
Is 18V available at CN261 pin 1,2,3,4,5?
NO
YES
Check peripheral circuits of IC804.
Is 3.3V available at IC804 pin 13 and pin 78?
NO
YES
Is 3.3V available at IC804 pin 9?
NO
YES
Is the 7.37MHz clock inputted into IC804 pin 12?
NO
YES
Does Pin 1 of IC804 output Hi?
Is the collector of Q805 Low?
When a power supply is turned on, is the pulse taken out
from IC804 pin 24 to IC401 C1?
Is a pulse returned from IC401 D3 to IC804 pin 25?
Check the power supply.
Check peripheral circuits of IC251.
Check the power supply.
Check peripheral circuits of Q151 to Q157 and IC221.
Check peripheral circuits of IC801.
Check peripheral circuits of X801.
NO
Check peripheral circuits of IC405.
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