HP 1100AHP - Manual (Page 145)

C4224-90962 Functional checks 143
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.
Heating element check
Paper passes between the heating element and a soft pressure roller to fuse toner to the
paper. To verify that the heating element is functioning correctly:
1 Unplug the HP LaserJet 1100 Printer for at least ten minutes.
2 Verify that the thermistor connector (Figure 5-3) is seated into both the printer chassis
and the ECU (for printer disassembly instructions, see Chapter 4, “Removal and
replacement”).