hp designjet T770 service station does not unlock

[eclengcntr]

HP designjet T770 service station does not unlock

[D Hook]

Are you trying to move the carriage assembly manually?  Are you able to use the menu and tell the printer you want to change the printhead(s)?  Not sure what the end goal is here.  If the printer is working you can load paper and while the carriage is moving to check the paper, turn it off using the switch on the back when the carriage is out of the service station.  Then you can move it by hand.

If you're trying to move the carriage manually with the printer off, you have to remove the right hand cover first.  Then on the back of the printer there is a hole that you insert a t-10 driver into and rotate to uncap the printheads and allow the carriage to move.  It's not difficult but you'll want to download a copy of the Service Manual to get a visual on it.  Just google "Designjet T770 Service Manual" and you can get a free download.  The picture is on page 320 and it's called an "uncapping screw".  Not sure why HP didn't provide a hole in the plastic to allow this without removing the cover.