Two things to try out.
Probably the easiest thing to do is to check the printer driver settings on your computer. Your printer driver has the option of printing in color or exclusively mono (black and white). Since your printer is printing, but only in mono or black mode, it seems like the printer driver would be the first place to start.
Secondly, it is possible through the web interface for the printer to specify that the output color is Auto, Color or B&W. It's possible you might have inadvertently changed this while you were resetting your machine after installing the replacement parts. (one can also do this through the Menu settings)
Go to the web interface by typing into your web browser http://xx.xx.xx.xx
, where xx.xx.xx.xx is the IP address of your printer. You may need to logon to the printer through the web interface. I believe the default password is access
You should find an option for Printer Settings. Mine is in the right hand column near the top, Click on that link.
You might also try typing in the following link where xx.xx.xx.xx is the IP address of your printer. http://xx.xx.xx.xx/fax/printermain.html?id=outputcolor
The leftmost tab for the Printer Settings is Output Color. Make sure that Output Color is set to Auto rather than B&W. If it is set to B&W, you will not be able to print in color.
Hope this helps you out.