Latch Failsafe; Cleaning The Printer - HP Engage One Retail System 143 Hardware Reference Manual

Latch failsafe

In the event that the receipt cover becomes stuck, the printer has a failsafe to release the cover's latches.
Using a thin pointed object, press the rectangular button adjacent to the printhead. With enough pressure, the
latches should release, and the receipt cover should open.

Cleaning the printer

Because of the way the printer sits while in use, it is likely there will be buildup of paper and other debris from
the knife. HP recommends that you keep the printer in working order by periodically cleaning the debris from
the printer.
To clean the printer, open the cover, remove the paper roll, and then use a can of compressed air to blow the
debris out from the bottom plate where it accumulates.
50 Chapter 4 Using the column printer