As above - I tried to fix this by turning it off, turning the key to program and holding down the #1 3 7 and 9 keys simultaneously. Turned the power back on and it moved the till roll on. Then I held down #1 and Clerk ID and turned the key back to register. I now have no display at all. Any ideas?

Phyl, April 2012

Sounds like the battery is faulty. Make sure it gets changed every four years. If you want to change it yourself and clear the error, the G215 service manual is here:

http://the-checkout-tech.com/manuals/cashregisters/JCM1.php

Registerman, April 2012