Had the same problem. (its a work around without removing the waste ink pad)
Took alot of work but I fixed it.
Frist thing you need to know that error means your ink waste pad is
full. Its a $75.00 to replace but there is a work around it.
You will need this free app. SSC service utitlty.
http://inkjetprinterhelp.us/epsonSSC.html Its a great app.
Instrusctions are on the website there.
You will also have to Open the access panel on the rear of the printer (remove screw) and
look inside carefullly with a flashlight. You will see a tube (down and
to your left) coming from the cleaning pump and it will have an open
end on it. This is the tube that
delivers ink to the waste pad.
Use a piece of coat hanger wire or equivalent, and fish out this
piece of tube. Bring it to the outside of the printer, thru the access
panel.
Find yourself a suitable container
(Tupperware or a plastic cup or jar) that is not too tall. Put the tube
into this container and secure the tube and container so they won’t
come apart or
lose connection if the printer is moved.
If you wish you can make a hole or notch in the access panel cover so it can be replaced.