Oki MC770 series Maintenance Manual - page 173

45376001TH  Rev.1 

172 /

Oki  Data  CONFIDENTIAL

7. Troubleshooting and repair procedure

7.5.4. (3) Paper feed jam (error code E130: 1st tray)

(3-1) Jam occurs immediately after the power is turned on. (1st tray)

Check item

Check work

Action to be taken 

at NG

(3-1-1) Check condition of the paper running path

 Paper running path 

of the front unit

Open the front cover check if paper is not 

jammed in the paper running path.

  Remove  the 

jammed paper.

(3-1-2) Check condition of the mechanical parts

 Check the sensor 

levers of the paper 

entrance sensor 

1 and the paper 

entrance sensor 2.

  Check if shape and movement of the sensor 

levers have any abnormality or not.

Replace the 

sensor lever with 

the good sensor 

lever.

(3-1-3) Check condition of electrical parts

Check the detection 

condition of the 

sensor signal.

Confirm that the sensor signals are normally 

detected by using the Maintenance Menu 

SWITCH SCAN function.

  Replace  either 

the PU board 

or the front 

sensor board 

(RSF PCB) 

or connection 

cable.

Check output signal 

level of the paper 

entrance sensor 1 

and that of the paper 

entrance sensor 2.

    Check for the following signals at the FSNS 

connector 

 of the PU board.

Pin-4: Paper entrance sensor 1 

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)

Check the 5V power at the FSNS connector 

of the front sensor board (RSF PCB).

Pin-1: 5V power supply 

Pin-5: 0VL

Replace the 

connection 

cable.

(3-2) Jam occurs immediately after the paper feed is started. (1st tray)

Check item

Check work

Action to be taken 

at NG

(3-2-1) Check condition of the paper running path

Paper running path 

of the front unit

  Check if paper is jammed or not in the paper 

running path.

  Remove the 

jammed paper.

(3-2-2) Check condition of the mechanical parts

Check the sensor 

levers of the paper 

entrance sensor 

1 and the paper 

entrance sensor 2.

  Check if shape and movement of the sensor 

levers have any abnormality or not.

Replace the 

sensor with the 

good sensor 

lever.

Check the separator 

assemblies of the 

feed roller, the 

pickup roller and the 

tray.

Check if any foreign materials such as paper 

dust on the surface of the feed roller or of the 

pickup roller or not. 

Remove the 

foreign material.

Check if the feed roller or the pickup roller has 

worn out or not.

Replace the 

separator 

assemblies of the 

feed roller, pickup 

roller and tray.

(3-2-3) Motor operation check

 Paper feed motor

Confirm that the paper feed motor works 

normally by using the Motor & Clutch Test of the 

self-diagnostic mode.

  Replace the PU 

board or the 

paper feed motor.

Paper feed motor 

driver

 Remove the HP_PSZCL connector 

 of the PU 

board and check the followings at the connector 

side.

Several M

Ω between pin-1 – FG. 

Several M

Ω between pin-2 – FG. 

Several M

Ω between pin-3 – FG. 

Several M

Ω between pin-4 – FG. 

Replace the PU 

board.