If blinking light then remove both cartridges and power off using the square button at the back.
Check that the printer Queue has no jobs - if there are jobs you need to cancel and delete them in the printers Queue.
Insert Only the Black cartridge, then power off and on and then see if you have a solid yellow. You can check this by powering off the printer using the black button and powering on again.
You should have a solid yellow light.
Remove the Black and insert the Color and power off using black button and then power on. (same procedure)
You should have a solid yellow light
---If you have any blinking lights on any of the cartridges then you need to replace the cartridge--
If there are no blinking lights then
Insert both cartridges - power off and on again and again you should have a solid yellow.
Now send a print job