No.	Jumper plug JP33A	Meaning
1		The motor start/stop option is not selected. The spindle motor is started when DK512C power is turned on. (Note)
2		The motor start/stop option is selected. The spindle motor can be started or stopped by using SCSI command.

As shipped from the manufacture, this jumper is installed in position#1 (option not selected).

When the motor start/stop option (No.2) is selected, the drive enters the motor stop state when its power is turned on.
Use the Start/Stop Unit (1BH) command to start or stop the drive.

(Note)

When motor start/stop option is not used, the controller does not respond to the host about 25 sec from Power turn-on to Drive Ready.

SZ184 PCB Jumper Location