NEC MultiSync LCD1550V Service Manual page 62

Continue
Check the CPH clock output to CN2 and CN3
pin 26 from U3 pin 123 at TTL level.
NG
OK
Proceed section 9 "Checking the resolution
change IC movement".
Printed wire broke between U3 pin 123
and CN2, CN3 pin 26.
6-8
Failure point