P04-513 is an ink overflow error.
the easiest way to fix it is to run the drum dry.
here is how:
1. turn the machine off by the power swith.
2. hold the left and right print position buttons and turn on the machine.
3. when the machine starts it will show you some numbers.. perss either the clear or yellow reset button to show 0000
4. now enter 81 and press start and the machine will make a master.
5. once the machine is done press the clear or yellow clear button to return to 0000
6. next make suer you have plenty of paper and enter 888 and press start.. the machine will start making copies of the test pattern. (if it jams a lot you may want to use speed 1 or go to step 4 and use code 80 instead)
once the copies start coming out light you can press the stop button and when the machine stops turn it off and back on normally.