Sony XR-55X90K Service Manual page 20

TROUBLESHOOTING
1.2 No Power u-com Failure
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Check P_ON_#2
no
CL417 Voltage.
Is the voltage >3.0V?
yes
Check P_ON_HL
no
CL415 Voltage.
Is the voltage >3.0V?
yes
Check ORESETB
no
CL416 Voltage.
Is the voltage >3.0V?
yes
Check X_BL_MUTE
no
CL412 Voltage.
Is the voltage >3.0V?
yes
Change IC401
Change IC401
Change IC401
SOC Muffin 5 (IC1000)
problem.
Check BL_ON
no
CL420 Voltage.
Is the voltage >3.0V?
yes
END
u-com IC401 is working OK
Change IC401
20
SYS SET