Sony BKDM-3020 Maintenance Manual page 27

Status code
MSB LSB
Operating state
(Example) Boot program version V1.30
Effect program version V1.50
MSB
Time
Indicates that the MPU-72 board is in operating failure.
In this case, replace the board with a new one.
(For the replacement procedures, refer to the section 2-6.)
1-8. Switch Settings on Boards and LEDs Description
LSB
System debugging
Boot V 1.30
No display
Effect V 1.50
System debugging
Version number
1-19 (E)