No Cartridge
From Cricut Hacking Wiki
Problem
When purchasing a used Cricut or from someone who has upgraded to the latest model, a cartridge is not included. This makes it very difficult to test if the unit works as expected.
Solution
By carefully shorting out a few wires in the Cartridge port it's possible to take advantage of the built in Cartridge "George and Basic Shapes". See the Reference links below to create your own.
- CAUTION: There is a risk of damaging your machine if you connect the wrong contacts.