Hidden Serial Number Mode; Update Mode (By Disc) - Marantz M-CR603 Service Manual

9. Hidden serial number mode

Serial number writing mode.
This mode is for production only, not described in detail.

10. Update mode (by disc)

Firmware update disc by.
When you replace the ETHERNET PCB ASS'Y (8U-310055S), you need software updates.
Refer to [ VERSION UPGRADE PROCEDURE OF FIRMWARE "1. How to update by disc" ].
Upgrade by DPMS. This mode describes a display only.
To exit this mode, unplug the power cord.
Startup display
"Disc Update Mode" displayed for 5 seconds.
The tray will open.
Insert disc.
The following states are displayed
Display update file.
Updating display
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