Pc/If Not Operating Correctly - Oki OKIFAX4550 Maintenance Manual

4.1.11 PC/IF not operating correctly

11: PC/IF does not
operate correctly
Pin 11 of CN11
(BUSY-P) is near 0V
Yes
Waveform of pin 1 of
CN11 (STB-N) is similar to
Figure H.7(2/2)
Yes
Signal output waveforms
of pins 4, 8 of IC20 are
similar to Figure H.8(1/2)
(IC20-8: ACK, IC20-4: FLT)
Yes
Check CN11 connection.
41309401TH Rev.4
No
Pin 11 of IC20 is near 0V
Yes
Replace IC20.
No
Check CN11 connection.
No
Signal input waveforms of
pins 3, 9 of IC20 are similar
to Figure H.8(1/2)
(IC20-9: ACK, IC20-3: FLT)
Replace IC20.
No
Replace IC2.
Yes
No
Replace IC2.
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