C0500 is a fuser warm up failure code. The procedure to reset is simple. First look at the right side edge of your control panel. This is where the meter count is and the "slide" that controls how dark/bright your display screen is. Now just to the left or front side of where the slide is you will see a small hole in the panel. You need a small paper clip or a tooth pick to insert into the hole. Next with the machine turned on and showing the code, insert something into the hole until the screen goes blank and begins to restart. You should see something that resembles the copier sitting on top of the globe. Keep watching the screen and at the far left side of the screen there will appear a small dot. As soon as the dot appears press the 3 key. You should now see a screen with several boxes. At the lower left is "Trouble Reset" - Press this box to reset the code. Do this reset procedure ONLY 1 time for every 10 minutes. If the code comes back you can try again in 10 miutes. If the fuser is heating and the machine just can not "see" it
then you can do further damage to the machine if you try to reset several times very quickly. If the machine warms up and makes copies you are all set. If the code comes back you have a failure in the fusing unit and will need it repaired.
This procedure works on the Di250 Di250F Di251 Di251F Di350 Di350F Di351 Di351F.
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