5. IC301 TROUBLESHOOTING
VFD display check
Refer to power troubleshooting
Check or replace R302
Check IC603 pin91 STB, pin57 Data, pin56 CS
YES
YES
NO
YES
NO
NO
Check the power supply
to IC301 pin9, 50, 51
Check IC301 pin7 FOSC
Check CON301 pin7 STB, pin8 Data, pin9 CS
NO
NO
Check
IC301 pin1 CS, pin3 STB
pin2, 4 Data
OK
3-6
ELECTRICAL TROUBLESHOOTING GUIDE