I have problem with my canon copier image ready 5020. error E000004-0000 how do I fix it i'd tried to press 2&8 but its said "Download Mode"

Error E000004 is a fuser related code and is most parts just caused by a paper jam in the fuser area. Before you begin to try and clear the internal flag you must make sure there is no paper or no obstruction stuck in the fuser area. With the power off rotate the fuser model handel to see if any aper or obstruction exsists. Clear it carefully if there is. At any time NEVER USE a knife or sharp object to clear a jam. Common sense I know, but few practice it. Once you clear the paper jam you can see if clearing the flag is the magic you need. If the next stages fail contract a local Canon trained tech to troubleshoot the real source of the error. Clear the error flag do the following steps DO NOT touch any thing else DON'T adjust any numbers. Turn machine on. When main screen apprears press Additional Functions button (*) let go. Press 2 and 8 together let go. Press Additional Funtions button (*) again. Screen should say Service Mode Level 1. Press these screen buttons in the following order. Copier, Functions, Clear, ERR then press OK in lower right corner. Machine will apprear as if nothing has happened but it has. Shut machine off at side. Turn on. Flag is cleared. If code reappears get professional help. This is a fuser code therefore we don't want a fire or anything else happening. Doing this clear you have 30 seconds before macine shuts off. It takes timing. Good Luck.