Support Code 6004 generally means that there may be foreign material (such as scraps of paper) inside the printer. However, if no such material is found, your printer will require service.
Solution
Follow these steps to fix your printer error
Turn off your printer and unplug it.
Open the scanning unit / cover.
Using a flashlight, check for any scraps of paper or other foreign material. If you see any, remove it.
If the issue isn't resolved after following the steps above, your printer will require service.
There are two options currently available to you.
Warranty Service – If you are within the 1-year manufacturer’s warranty and have your proof of purchase you are entitled to service or replacement. If you have purchased a CarePak Canon extended warranty, you may be entitled to additional options. Please create or log into your Canon Account to obtain service.
Out of Warranty – If you are outside of your warranty period, you may qualify for purchasing a replacement through the Canon Upgrade Program. Please contact our Sales group to inquire about your upgrade options at 866-443-8002.
To verify your support options please create or log into your Canon Account.