HP LaserJet Enterprise M4555 MFP series - Manual (Page 265)

Service settings
These items in the control-panel menus can help with troubleshooting if the corrective action taken under
the Error Codes section is unsuccessful. They are intended to be used when an HP service
representative is assisting you.
Settings in the Troubleshooting menu
Open the Administration menu, and then select the Troubleshooting menu.
Troubleshooting menu settings T.30 Trace: The T.30 trace is a printed report which produces a record of all the
communications between the sending and receiving fax machines for the last Fax
transmission or reception. The report has many technical details which are usually
beyond the scope of most users. However the report contains detailed error codes
and other information that might be useful in troubleshooting a particular problem
related to sending or receiving a FAX. The report contents might be requested by
an HP service representative when trying to determine the cause of a problem and
will help to determine the appropriate action.
Transmit Signal Loss : This selection compensates for phone line signal loss. It is not
recommended to modify this setting unless requested to do so by an HP service
representative as it might render the fax inoperable.
V34 : This setting has two values (Normal and Off) that control the modem's baud
rate. The Normal setting allows the modem to select (negotiate with the other
modem) any of the supported baud rates up to 33,600 bps. The Off setting sets
the baud rate to 14,400 bps. This setting remains set, until changed.
Speaker Mode : This service setting has two modes, Normal and Diagnostic. In
Normal mode, the modem speaker is turned on during dialing through the initial
connection and then shuts off. For Diagnostic mode, the speaker is turned on and
remains on for all fax communications until the setting is returned to Normal.
Settings in the Resets menu
Open the Administration menu, and then select the Resets menu.
Resets menu settings Restore Factory Telecom Settings or Restore Default Telecom Settings : This selection
resets several menu changes back to their default settings. This includes the
maximum baud rate, ring-burst off time, V.34, speaker mode, and transmit signal
loss.
Firmware upgrades
The firmware on the fax accessory can be updated. Fax firmware updates occur as part of an overall
product firmware update. See the product user guide for more information.
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