Canon LBP351 Series, Service Manual

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Obtaining Debug Log
Function Overview
Debug logs (hereinafter "Sublogs") are logs that record the internal operations of the Main Controller, and are used to analyze
program operations and used by developers to identify problems.
When a problem that is difficult to reproduce occurs, collecting a Sublog immediately after the problem has occurred on site can
increase the efficiency of analyzing the problem and reduce the time it takes to deal with the problem.
Be sure to collect the debug log when the Support Dept. of sales company so instructs.
Note that there is no need for service technicians to check the content of collected debug log.
Sublog
It is available only when the Sublog Board is installed on the Main Controller PCB.
When the Sublog Board is not installed, log is not saved anywhere.
It is stored in the Sublog Board and its content is stored even when the power is turned OFF to be displayable when the power
is turned ON again.
The Sublog Board has a limited capacity and when the log exceeding this storage number is attempted to be stored, the log is
deleted in the order of length of time stored.
How the log is written
The RAM of the Sublog Board is directly overwritten by a processing of the Main Controller. The logs are not erased when
the power of this machine is turned OFF, because a button battery is included.
Main Controller Board
Conditions for collecting logs
Conditions where log collection is valid
Collection of debug log is effective in the following cases:
• Neither the Support Dept. of sales company nor CINC can reproduce the trouble that occurred at the customer site.
• When the error frequency is low
• When a failure of firmware, etc. is suspected, rather than a mechanical failure or electrical failure
CAUTION:
If the procedure for reproducing the failure is clear and the Support Dept. of sales company and CINC can reproduce it,
collection of debug log is not necessary.
Conditions where logs cannot be collected
Logs cannot be collected under the following conditions:
• Service mode screen cannot be accessed
• The machine cannot recognize a USB flash drive.
• The machine does not have a USB port.
7. Troubleshooting
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