Lexmark C77X, Service Manual

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Service Manual
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Service checks
100.01 ITU error service check
A 100.01 ITU error indicates that the printer did not detect the ITU belt home sensor. Before proceeding with this
service check, make sure that the Second Transfer Roll is correctly installed. After you reinstall the Second
Transfer Roll, check to see if a 100.01 ITU error is still displayed. If a 100.01 ITU error is still being displayed,
continue with this check.
The ITU has an optical sensor that watches for a piece of reflective tape on the inside of the image belt. This
tape is read every revolution of the belt. If a signal is not received from the belt sensor within a certain time
period, the printer posts an error due to the loss of signal. There are several causes for the loss of signal. First,
the belt has tracked too far to the front or rear of the printer. In this case, the belt is still turning, but the reflective
tape is no longer passing within view of the belt sensor. This is considered a belt tracking error and is initially
posted as a 100.02 ITU Error. The other causes of a signal loss could be a belt stall, meaning the belt is not
turning, or a true signal loss, which would be due to a bad sensor, broken cable, loose connection, or bad
system board. These other causes post as a 100.01 ITU Error.
To assist the printer in determining the cause of a signal loss, there is a buffer that records the belt position for
the last 50 revolutions. If the printer loses the belt signal, it refers to the buffer. If the buffer shows significant
mistracking before signal loss, it will post a 100.02 ITU Error. If the buffer shows that the belt has been tracking
in the center before signal loss, it posts a 100.01 ITU Error. Due to memory restrictions, the buffer is not saved
during POR. This means if a printer posts a 100.02 ITU Error, so the belt is tracked off, and the customer or
servicer turns off the printer to clear the error, when the printer starts up, it will still not see the belt signal and will
now post a 100.01 ITU Error because the buffer is empty. When servicing a printer for a 100.01 ITU Error, it is
important to view the error log. See
“Display Log” on page 3-29 . The error log can only be displayed at this
point. Do not try to print the log. Look for past occurrences of 100.01 ITU Errors preceded by a 100.02 ITU Error.
990.01 < device > This error message indicates that an equipment check condition has occurred in the
specified device, but the error is unable to identify the exact component failure. Go to
“990.01 error service check” on page 2-67 .
Note : < device > can be one of the following:
• Duplex option. See “Duplex option service check” on page 2-83 .
• Tray x (where x =2, 3, or 4). See “500-sheet drawer option service check” on
page 2-73 .
• Output Expander or StapleSmart finisher—Output bin x (where x =1). See
“Output expander option service check” on page 2-92 or “StapleSmart
finisher service check” on page 2-113 .
• 5-Bin Mailbox—Output bin x (where x =1 through 5). See “5-bin mailbox option
service check” on page 2-69 .
Go to the service check for the device indicated.
Step Actions and questions Yes No
1 Make sure all packing material is removed from the
printer. The detensioner is located underneath the
toner cartridges. Make sure the ITU detensioner is
removed. Remove the detensioner by pulling up on the
red handle on the right side of the ITU.
Note : All the print cartridges must be removed to gain
access to the detensioner packing material.
Has all packing material been removed from the
printer?
Go to step 2 Remove any
remaining
packing material
from the printer.
Error codes and paper jam messages (continued)
Error code Action