I changed the blue toner and now it prints with the backgroud blue on every page over what I was printing. It's a Kyocera FS-C5030N

You need to reset the toner counter. This is done through the Menu button and selecting Life Counters. The instructions on how to do this are found in the Advanced Operators Guide on page 2-75. The link below will take you to the manufacture's website where you can download it.
http://usa.kyoceramita.com/americas/jsp/Kyocera/resource_details.jsp?pid=14192&rid=14764

Resetting the Toner Counter

The toner containers must be replaced when the printer displays the Low toner or Replace toner message which will be given depending on the color of toner. The Low toner message will be shown as a pre-warning that the toner is running out and the printer will soon stop, at that time showing Replace toner. If you replace the toner container before Replace toner is displayed, you must manually reset the toner counter as explained below. Note that if you reset the toner counter before the toner container is replaced, the subsequent toner warnings will not be indicated correctly.

I hope this is helpful,

Shawn

Clean waste toner,Drum blade.

the charger is broken...

I’m happy to assist further over the phone at https://www.6ya.com/expert/norman_d2fa496dce30c65d

Push in the charge corona assy. Its behind the left door. Each color has a cleaning rod and charge assy. I've seen this more than once.

clean the corotron and perform drum refresh

Generally it means you need a new developer unit.

there are a good few possibilities... your cheapest route is to call a local service tech... anything I tell you is going to cost you more... call him and see what he says... but I am leaning towards bad ram best case and worst case a blown main board...

I’m happy to assist further over the phone at https://www.6ya.com/expert/norman_d2fa496dce30c65d

Replace the developer unit and that will fix it.

What memory dimms have been fitted.
Print status page see top right. May need more memory and a hard drive.
cheers

Check cable is secure from pc to printer

Check printer can print a status page via printer keypad and is online/ready

If these are ok then it is a print driver issue

Turn off printer, Unplug usb, delete and reinstall print driver