Oki B 4100 Maintenance Manual page 304

A
The error counter of LCD
stops counting up?
Receive signal appears
across L1 and L2?
Receive signal appears
across CN3-19, 20 (R) and
CN3-7 (GND) of NCU
board?
Replace MCNT Board.
Signal route:
CN6-A6, B6 (R) IC12-3
IC8-60 (RXA1)
IC8-26 to 33 (AD0 to AD7)
Return to section 7.2.1
40055101TH Rev.4
RX (Receiver)
Yes
No
No
Yes
No
Yes
Replace NCU Board.
Yes
Replace MCNT Board.
RX End
Check the line.
Yes
Solved?
No
Signal route:
CN1-3, 4 RL1-8, 5
T1-1, 3 T1-2, 6
CN3-19, 20 (R)
Possible cause:
CML signal
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