Oki OKIFAX4550 Maintenance Manual page 539

4.1.5 Recording paper running system NG
5: Recording paper
running system NG
Recording paper feed is NG
No
Outlet error
No
Toner near end
problem is identified
Input of pin 36 of IC2
repeats 5V and 0V cyclically
along with drum rotation
Yes
Replace IC2.
41309401TH Rev.4
Yes
Motor is started?
No
Input waveforms of pins
17, 26 of IC9 are similar to
Figures H.4(1/2, 2/2)
Yes
Replace IC9 or F1.
Yes
No
Yes
Pin 2 of TR512 changes
No
from 0V to 5V when
recording paper is fed
No
Replace IC2.
Voltage of pin 3 of TR513
is approximately 0.7V
lower than pin 1 when
No
recording paper is fed
Replace TR512.
No
Check CN6.
Yes
Yes
Replace TR513.
Input of pin 28 of IC2 changes
from 5V to 0V when the
outlet sensor is moved
Yes
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