Rap 20E Printer Alarm 4 - OKIDATA OF2600 Service Manual

RAP 20E Printer Alarm 4

START
"PRINTER ALARM 4" appears on the LCD display.
Power OFF, then power ON.
After a short delay, does "PRINTER ALARM 4" appear on the LCD display?
YES Remove the fuser assembly for testing (Refer to the Action Items Diagram).
Check the resistance between the thermistor contacts. At room temperature,
it should read approximately 200 Kohms.
Is the resistance correct?
NO Replace the fusing unit.
YES Does the thermistor contact correctly touch the contact assembly when the
fusing unit is installed? (Refer to the Action Items Diagram)
NO Adjust the contacts as necessary.
YES Refer to Action Item 9.
NO Does PRINTER ALARM 4 occur approximately 60 seconds after powering ON the unit?
YES Is the heater lamp of the fusing unit ON? To check, remove the stacker cover.
Overide the cover interlock. Light can be seen from the ends of the fuser
lamp is ON.
NO Is the heater or thermistor open? Measure the resistance between the two
heater contacts. Normal resistance is approximately 0 ohms.
replace the power supply board.
NO Refer to Action Item 9.
Replace the printer control board.
YES Replace the fusing unit.
NO Is the AC voltage from the fuser present at the contact assembly?
NO Replace the printer control board. If the problem persists,
YES Replace the fusing unit.
Service Guide OF2200/2400/2600
Chapter 2 Failure Analysis
Page: 73
when the heater