Sanyo HV-DX300A Service Manual page 7

TROUBLESHOOTING
2. SYSTEM CIRCUIT
A. LED DISPLAY
No LED display.
Is 5V obtained at IC701
pin #9, 25?
YES
Oscillation at IC701pin #1?
YES
Specific GRID/SEG doesn t function.
YES
GRID output at PORT of IC701?
YES
SEG output at PORT of IC701?
NO
Check R588, D857, L503, L860
NO
Exchange IC701.
NO
Check IC 701 pin #22~24, 27,
28, 30, 31.
NO
Check IC 701 pin #10~12, 14~21.
Exchange IC701.
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