OKI C931

Jam occurs in the middle of paper running path.

Motor operation check

Check item	Check work	Actions to be taken at NG
Feed motor driver, belt motor driver and fuser motor	Confirm that the hopping motor, belt motor and fuser motor work normally by using the Motor & Clutch Test of the self-diagnostic mode. Check if any load exists or not.	Replace the PU/CU PCB, the faulty motor of either hopping motor or belt motor, or the belt unit.
Feed motor, belt motor	Remove the FDMRG2CL connector of the PU/CU PCB and check the following at the connector side. Several MΩ between pin-1 – FG Several MΩ between pin-2 – FG Several MΩ between pin-3 – FG Several MΩ between pin-4 – FG Several MΩ between pin-5 – FG	Replace the PU/CU PCB.

Jam occurs immediately after paper has reached the fuser.

Motor operation check

Check item	Check work	Actions to be taken at NG
Fuser motor	Confirm that the fuser motor works normally by using the Motor & Clutch Test of the selfdiagnostic mode. Check if any load exists or not.	Replace the PU/ CU PCB, fuser motor, fuser unit, and/or fuser driver gear train (oneway gear).

Temperature control while fuser belt running

Check item	Check work	Actions to be taken at NG
Detected temperatures of the fuser	Check temperatures detected at the fuser belt in the self-diagnostic mode. Has abnormally low (lower than the room temperature) or high (250°C) temperature been detected?	Replace the fuser unit or PU/CU PCB.

Check the installation condition of fuser unit

Check item	Check work	Actions to be taken at NG
Fuser unit	Check that the fuser unit is installed normally. (Is it pushed in down to the bottom-most point?)	Install the fuser unit correctly in the printer.