Ricoh MPC 2800 AT-C2, Field Service Manual, Page: 352 / 856

Scanner Test Mode
SBU Test Mode
Output the SBU test pattern with SP4-807-001 to make sure the scanner SBU control operates correctly.
The SBU test pattern prints out after you have set the SP mode settings and pressed the start key.
• The CCD on the SBU board may be defective if the copy is abnormal and the SBU test pattern is
normal.
• The followings can be the cause if the copy is normal and the SBU test pattern is abnormal:
• The harness may not be correctly connected between the SBU and the BICU.
• The BICU or SBU board may be defective.
IPU Test Mode
You can check the BICU board with the SP mode menu, SP4-904-1.
If no error is detected, the test ends. Then the completion code shows in the operation panel display. If an
error is detected, the test is interrupted. Then an error code shows. The table below lists the completion and
error codes.
SP4-904-1 Register Access
There are 16 bits switches in this SP. Each bit indicates a different CPU. The error result is displayed on the
operation panel as a decimal number.
0: Normal, 1: Error
SP4-904-2 Image Path
There are 16 bits switches in this SP. Each bit indicates a different CPU path. The error result is displayed
on the operation panel as a decimal number.
0: Normal, 1: Error
Errors may be caused by the following problems:
1. Short circuit on the signal lines
• When the BICU board is installed, a pin or two on the ASIC is damaged.
• Some conductive matter or object is trapped among the pins.
• Condensation
2. Destruction of circuit elements
6. Troubleshooting
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