Hello kkoester. I understand the printer is unable to print in colour. It's fair to assume the issue could be hardware-related, based on your description. To commence troubleshooting, please follow the steps in this HP document: http://h10025.www1.hp.com/ewfrf/wc/document?cc=us&lc=en&docname=bpu04822
Please respond when you complete this troubleshooting. I'm only here to help!
Mario