Xerox Phaser 3100MFP Service Manual page 219

General Procedures and Information
Registration
Figure 10
The registration sensor [A] detects the leading edge of the paper and synchronizes paper feed
with the writing of the image on the drum, so that the image and paper match up properly. This
sensor also detects paper feed jams.
Phaser 3100 MFP 04/08 6-71