TROUBLESHOOTING
2. SYSTEM CIRCUIT
A. LED DISPLAY
No LED display.
Is 5V obtained at IC701 NO
pin # 9, 25?Check L703, pin#6 of PJ701
YES
NO
Oscillation at IC701 pin #1? Exchange IC701.
YES
NO
Is there KEY/SEG signal?Check PCB
YES
NO
KEY output at PORT of IC701?Check IC 701 pin #6, 7, 8
YES
NO
SEG output at PORT of IC701?Check IC 701 pin # 10-12,14,15
Exchange IC701.
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