Printronix L1024, Maintenance Manual

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13–33 Chapter 13 – Troubleshooting Guide
paper guide. If it is not binding on the hole, replace the lever and its
stand.
b) If the lever is still binding or striking the edges of the hole in the fuser
paper guide, replace the guide.
2) Reset the paper into the tractor assembly. Make sure the leading edge of the
paper is not torn or wrinkled, since this will cause jams as the paper enters the
fuser.
3) Make sure the paper is stretched tightly between the tractors so that it is not
bowed. Bowed paper will tend to catch as it enters the fuser.
4) Check the fuser paper guide to make sure it is not bent or damaged and
replace it if needed.
c. The paper is jammed, bowed, or buckled between the OPC drum unit and the fuser.
This causes the paper to lift off of the TOF lever, which causes a paper jam error.
NOTE: During the registering (setting) of top of form, the tractor pulls the paper
through the printer until it reaches the fuser. Once the paper has entered
the fuser, the fuser is the drive mechanism for the paper. It pulls the paper
through the printer at a slightly faster rate than the tractor does, thus
keeping the paper tight between the tractor and the fuser.
If the rollers in the fuser do not turn, or the rollers are worn so that their diameter is
smaller, the tractor will pull the paper through the printer faster than does the fuser.
This causes the paper to bow upward and lift off of the TOF lever, or strike the paper
jam sensor. When the printer is open, this might not be visible, because when an error
occurs, the fuser opens and the paper tends to lay flat again.
To check for this bowing phenomenon, turn off the printer while it is still printing and a
number of pages have been printed. Do this while the printer is actually printing. The
fuser will stay closed and any bow of the paper will be visible when you open the
printer.
Verify that the rollers are turning by opening the top cover of the printer, defeating the
cover open switch, resetting the paper in the tractor, and resetting TOF. Turn on the
printer and watch the fuser as the top of form is being set. The fuser should be closed
and the rollers turning as the paper enters the fuser. If the rollers are not turning,
repeat this step and see if the drive belt, fuser drive clutch and gear, and electric clutch
are turning.
1) The fuser is not closing.
a) Replace the Engine Controller Board.
Step 1) is very unlikely. In order for step 1) to occur at this point, the printer
would have to fail its power-on self-test. The fuser cam motor is cycled during
the power-on self-test. If the fuser does not close and then open, a “FUSER
FAIL” error will occur. If this error does not occur, the Engine Controller Board
is faulty.
2) The fuser roller is not turning.
a) The drive belt is turning.
1] The drive belt is turning the drive pulley assembly but the
fuser roller is not turning.
a] The fuser drive gear in the pulley assembly is not
turning, but the belt pulley is turning. This indicates
that the drive pulley clutch inside the assembly is
defective, and the pulley assembly must be replaced.