Scanner Motor Fault Detection; Service Works; At Parts Replacement; Maintenance - Canon imageCLASS MF4890dw Service Manual

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Technical Overview > Laser Exposure System > Service Works > Notes on service works

■ Scanner Motor Fault Detection

This is the detection of faults in the laser scanner unit.
When the laser scanner unit falls into either of the following status, the engine controller
judges it as a fault in the laser scanner unit system and notices the status of fault to the main
controller.
The operations of the host machine are stopped.
1. Fault in BD input
At startup of the scanner, /BDI signal cannot be detected within 0.1 sec from the completion
of forced acceleration of the scanner motor.
2. Fault in startup
During activating the scanner motor at startup of the scanner, the motor rotation exceeds
the specified range (98.3 to 101.7%).
3. Fault in control
After startup of the scanner completes correctly, /BDI signal exceeds the specified value of
cycle 2000 msec consecutive times.

Service Works

■ At parts replacement

No work is required for this product at parts replacement.

■ Maintenance

No periodically replaced parts, durable parts or periodical service is set for this product.

■ Notes on service works

None.
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