44015503TH  Rev. 1 
194 /
Oki  Data  CONFIDENTIAL
7.  TROUBLESHOOTING PROCEDURE
7.5.2.(5)  Paper feed jam (error code 390: Multipurpose tray)
(5-1)  Jam occurs immediately after the power is turned on. (Multipurpose tray)
Check item Check work
Action to be taken 
at NG
(5-1-1) Check condition of the paper running path
 P
aper running path 
of the multipurpose 
tr
ay
 Check if paper is jammed or not in the paper 
running path.
Remove the 
jammed paper.
(5-1-2) Check condition of the mechanical parts
 Chec
k the sensor 
levers of the paper 
entrance sensor 2 
and the WR sensor.
 Chec
k if shape and movement of the sensor 
levers have any abnormality or not.
 Replace the 
sensor with the 
good sensor 
lever.
(5-1-3) Check condition of electrical parts
Check the detection 
condition of the 
sensor signal.
Confirm that the sensor signals are normally 
detected by using the SWITCH SCAN function 
of the self-diagnostic mode.
Replace either 
the PU board 
or the front 
sensor board 
(RSF PCB) 
or connection 
cable.
 Chec
k the sensor 
output signal level of 
the paper entrance 
sensor 2 and the 
WR sensor
. 
 Check for the following signals at the FSNS 
connector   of the PU board.
Pin-2: WR sensor 
Pin-3: Paper entrance sensor 2
Confirm that the above signal levels change 
when the sensor lever is operated.
Replace the 
front sensor 
board (RSF 
PCB)
Check the power 
voltages supplied 
to the front sensor 
board (RSF PCB)
Chec
k the 5V power at the CN connector   of 
the front sensor board (RSF PCB).
Pin-1: 5V power supply 
Pin-5:
 0VL 
Replace the 
connection 
cable.
Check item Check work
Action to be taken 
at NG
(4-2-4) Check the system connection
Paper feed motor 
drive cable
 Check the connection condition of the cable. 
Check if the connector is connected in the half-
way only or not, and check if the connector 
is inserted in a slanted angle or not. Check 
also that cables are assembled without any 
abnormality.
 Replace the 
cable with the 
good cable 
that normalizes 
the connection 
condition.
Paper feed motor 
drive cable
Check that any cable is not pinched during 
assembling of the printer. 
Remove the HOPSIZE connector no. 1 of the 
PU board and check the followings at the cable 
side. 
Short circuit between pin-1 – FG 
Short circuit between pin-2 – FG 
Short circuit between pin-3 – FG 
Short circuit between pin-4 – FG
 Replace the 
cable with the 
good cable 
that normalizes 
the connection 
condition.
Paper feed motor Remove the HOPSIZE connector 
 of the 
PU board and check that approx. 3.4
Ω
 can be 
measured between pin-1 -pin-2 at the cable end, 
and that approx. 5
Ω
 can be measured between 
pin-3 -pin-4 respectively. 
Replace the 
paper feed motor.