Make sure the drawer is not locked. Can you open from the lever underneath? Do they open the drawer when you print a daily report in Z mode? If not, they probably have the drawer fault that was common on this model. Take the drawer insert and tray out. you should see two white wires in the back of the drawer. If one of the wires has a cut in it, you will need to take it to a dealer. You might be able to get it fixed for free as it was as a factory fault.
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If anyone needs more information, the sharp XE-A303 manual is here:
http://the-checkout-tech.com/manuals/cashregisters/Sharp12.php
Registerman
August 2011
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