Oki OKIFAX4550 Maintenance Manual page 235

A
The error counter of LCD
stops counting up?
No
Receive signal appears
across L1 and L2?
Yes
Receive signal appears
across CN3-48 (R) and
CN3-14 (GND) of NCU
board?
Yes
Replace MCNT Board.
Signal route:
<46F>
CN10-A2 (R)→IC12-3→
IC8-32 (RXIN)→
IC8-87 to 95 (D0 to D7)
<R46>
CN10-A2 (R)→IC10-3→
IC6-32 (RXIN)→
IC6-87 to 95 (D0 to D7)
Return to section 7.1
41309401TH Rev.4
RX (Receiver)
Yes
RX End
No
Check the line.
No
Yes
Replace NCU Board.
Yes
Solved?
No
Replace MCNT Board.
Possible cause:
CML signal
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