Oki B4100 - Manual (Page 304)

40055101TH Rev.4 304 /
Receive signal appears
across CN3-19, 20 (R) and
CN3-7 (GND) of NCU
board?
The error counter of LCD
stops counting up?
RX (Receiver)
Return to section 7.2.1
No
Yes
Replace MCNT Board.
RX End
Receive signal appears
across L1 and L2?
Replace MCNT Board.
A
Possible cause:
CML signal
Yes
Replace NCU Board.
Yes
Solved?
Check the line.
Signal route:
CN1-3, 4
→
RL1-8, 5
→
T1-1, 3
→
T1-2, 6
→
CN3-19, 20 (R)
Yes
No
No
No
Yes
Signal route:
CN6-A6, B6 (R)
→
IC12-3
→
IC8-60 (RXA1)
→
IC8-26 to 33 (AD0 to AD7)