HP 3150 EN - Manual (Page 180)

178 Troubleshooting EN
Drum rotation functional check
The photosensitive drum, located in the toner cartridge, must rotate
for the print process to work. The photosensitive drum receives its
drive from the main drive assembly. To verify that the drum is
rotating:
1 Open the printer door.
2 Remove the toner cartridge.
3 Mark the drive gear on the cartridge with a felt-tipped marker.
Note the position of the mark.
4 Install the toner cartridge and close the printer door. The start-up
sequence should rotate the drum enough to move the mark.
5 Open the printer and inspect the gear that was marked in step 3.
Verify that the mark moved.
If the mark did not move, inspect the main drive assembly to make
sure that it is meshing with the toner cartridge gears. If the drive
gears appear functional and the drum does not move, replace the
toner cartridge.
Note This test is especially important if refilled toner cartridges have been
used.