Canon iR4570 Series, Service Manual

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Chapter 14
14-2
14.1.6 Checking the Units and Functional Systems
0007-9388
iR2270 / iR2870 / iR3570 / iR4570
Reader Unit
- Check the scanner unit (contact sensor, white plate, copyboard glass) for scratches, dirt, and foreign matter.
- Check the contact sensor unit to see if it moves smoothly and if it is free of dirt.
- Check to see if the contact sensor is free of flickering.
- Check to see that the scanner system is free of condensation.
Process Components
- Check to see that the drum unit and the developing unit are properly fitted.
- Check to see that the photosensitive drum is free of scratches and dirt.
Transfer Components
- Check to see that the transfer roller is free of wear, scratches, dirt, and deformation.
Fixing Assembly
- Check to see if the fixing film and the pressure roller are free of wear, scratches, dirt, and deformation.
- Check to see that the fixing thermistor is free of an open circuit.
- Check to see if the thermal switch is free of disruption in its electrical continuity.
Paper Feed System
- Check to make sure that there is no paper lint or foreign matter.
- Check to make sure that there is no buildup of paper around the pickup, feed, and separation rollers. See that they
are free of wear, scratches, dirt, and deformation.
- Check to make sure that the paper is free of a bent leading edge and is free of curling, waving, and excess moisture.
- Try using paper and transparency of a type recommended by Canon to see if the problem is corrected.
Mechanical
- Check to make sure that the load imposed on the drive system is not more than permitted.
- Check to make sure that the gears are free of wear and chipping.
Cassette
- Check to see that the cassette is correctly fitted. Check to see that the paper size is correctly set. Try replacing with
a fault-free cassette to see if the problem is corrected.
- Check to see that the movement of the holding plate of the cassette is normal and the plate is free of deformation.
- Check to see that the side guide plate and the rear guide plate of the cassette are fitted correctly.
- Check to see if the switch of the cassette heater is turned on (only if a cassette heater is mounted).
Service Mode
- Check to see that the various adjustment settings of the CCD are as indicated on the service label.
(COPIER>ADJUST>CCD>all items)
- Check to see if registration adjustment is executed.