Check the obvious reasons first: Does the printer have power? Is there paper loaded?  Is the cable to the PC that drives it connected? If all of these are fine, then it could be that communication to the check printer has failed.  Perform the following actions to resolve the situation:
 
1.) Disconnect the print session
2.) Power down the PC that hosts the print session
3.) Physically power down the printer
4.) If there is a print server, power it down by unplugging the power cable
5.) Power down the check secure device by unplugging the power cable
 
Restart the devices in this order:
 
1.) Printer
2.) Check Secure
3.) Print Server
4.) PC
5.) Start print session
 
If this does not resolve the issue, please contact the Systems Department.