Detecting Jams - Canon LBP-2000 Service Manual

CHAPTER 2
D. Detecting Jams
The feed paper sensor (PI201) is used to check the presence/absence of paper and to find out if
paper is moving correctly. It checks for a jam in terms of the presence/absence of paper over it at
such times as programmed in advance. When the CPU detects a jam, it will stop printing operation
and indicate the fact to the DC controller.
1. Pickup delay jam
The video controller will identify a feed sensor pickup delay jam or a registration sensor pickup
delay jam as a pickup delay jam.
• Feed Paper Sensor Pickup Delay Jam
The feed paper sensor (PI201) does not detect the leading edge of paper within a specific period of
time after the feeding roller starts to rotate to move paper.
• Registration Paper Sensor Pickup Delay Jam
The registration paper sensor (PI101) does not detect the leading edge of paper within a specific
period of time after the feed sensor detects the leading edge of paper.
• Feed Sensor Pickup Delay Jam
PF pickup clutch
PF pickup motor
Feed paper
sensor jam check
PF feed paper
sensor
• Registration Sensor Pickup Delay Jam
PF1 feed
paper sensor
Registration paper
sensor jam check
Registration paper
sensor (PI101)
2 - 70
/PRNT signal IN
Jam message ON
2nd sheet picked up
Pickup control
STBY
Normal
Figure 2-7-6
/PRNT signal IN
2nd sheet picked
Pickup control
STBY
Normal
Figure 2-7-7
Error
Jam message ON
Error