A few easy things to try. First off, have you power cycled the unit since checking for a paper jam? Often that will clear false errors. If not, look for the sensors. They should be somewhere along the paper path, and consist of a plastic lever that will be pushed down as the paper moves past them. Usually these levers have springs attached - if the spring comes off, it will register a paper jam. You'll probably have to take off some of the housing to get to them. I'm not sure this will help much, but since I found it I'll post it. The user's manual: http://edocutek.com/Manuals/DR6080_9080C_UG.pdf If the sensor needs replaced (most often due to something simple like a piece of plastic breaking on it), you can order new sensor PCB assemblies (sensor and its small control board) here: http://www.precisionroller.com/manufacturers/canon-dr6080.html They also sell a parts manual, but it's a bit pricey.
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