Lexmark 4500-00 Series, Service Manual

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Diagnostic aids
3-9
4500–E320/E322
Diagnostic tests mode
The diagnostic tests mode causes the printers internal tests to be
performed. If any of the diagnostic tests fail, a service indication is
posted. You can determine which test failed by accessing the
service code associated with the service error. The secondary
service code is displayed by performing a button press while the
service indication is posted on the operator panel.
If the printer completes all its diagnostic tests successfully, the Toner
Low light blinks. To exit diagnostics, turn off the printer.
While running diagnostics, the printer performs the following tests:
•
Standard memory test
•
Optional memory test
When the printer enters Normal or Demo modes, the total amount of
installed memory detected during the POST sequence is compared
with an NVRAM value representing the printer total installed
memory.
•
If the amount of detected memory matches the value stored in
NVRAM, the printer doesn’t perform a Memory Test during
POST sequence into Normal or Demo modes.
•
If the amount of detected memory does not match the NVRAM
value representing total installed memory, the printer assumes
the user has changed the printers memory configuration by
adding or removing optional memory.
To verify the new memory configuration, the printer performs a full
Memory Test and then updates the NVRAM value representing the
total installed memory.
Note: The printer always performs a complete Memory Test when
executing the Diagnostics Test.