The tool changer arm on my Matsuura MC1000V7 is rotating into position, the drawbar activates (release), but the arm doesn't drop down to complete the change. After a few seconds it generates the error:

3000 SEQUENCE TIME OVER.
CHECK NEXT SEQ. NUMBER.

SEQ. 11
IN MOTION OF ATC(M06)
2307 TOOL CHANGE DOES NOT FINISH IN 4.0 SECONDS.

3031 ATC INVERTER ALARM.

I suspect a bad solenoid but even after pouring over the manual I cannot figure out what activates the arm to drop. Any ideas?

I can remove the tool manually so the drawbar is releasing.