Xerox WorkCentre M20 Service Manual page 157

• ENGINE VER:1.00V
Pattern Test
This procedure is used during manufacturing only. Not to be used during service.
Shading Test
Use this procedure to test the CCD. If the image quality is unsatisfactory, perform this proce-
dure to check the operation of the CCD.
NOTE: Before performing the adjust shading test, ensure the DADF is lowered.
Perform the following:
1. Enter service mode, GP 3.
2. Select 'ADJUST SHADING'.
3. Press the SET UP button, then an image will be scanned.
4. After the scan, the CCD shading profile will be printed, Figure 1.
5. If the printed image is different to the CCD shading profile image, the CCD is defective.
Figure 1 Shading profile
Work Centre M20 Family
Error Rate
If the error rate is about to exceed the set value, the Baud rate is automatically lowered, by up
to a maximum of 2400 bps, to ensure that the error rate remains below the set level.
The rate can be set between 5% and 10%.
Modem Speed
The maximum modem speed can be set.
The machine will automatically lower the modem speed setting when communicating with a
machine that has a lower transmit/receive setting.
The default modem speed setting is 33.6Kbps. This default setting should not be changed.
Engine Test
Refer to Engine Test Mode Entry, GP 1.
Silence Time
In ANS/FAX mode, after a call is picked up by the answering machine, the machine monitors
the line. If a period of silence is detected on the line at any time, the call will be treated as a fax
message and the machine will begin receiving.
Silence detection time is selectable between limited (approximately 12 seconds) and unlimited
time. When '12 sec' is selected, the machine switches to receiving mode as soon as it detects
a period of silence. When 'unlimited' is selected, the machine waits until the answering opera-
tion is concluded even though a period of silence is detected. After the answering operation is
concluded, the machine switches to receiving mode.
Flash Upgrade
The firmware upgrade procedure has two methods, local and remote. For more information,
refer to Firmware Upgrade, GP 8.
Reset Passcode
Use this procedure to either disable or reset the system administrator passcode.
March 2004
6-13
General Procedures and Information
GP 6