This manual is very useful because it presents the technical specifications of the cd player, including the manufacturer of the reader, this helps if you need to replace it. It also displays the settings and layout of the circuit.
Manual was a good representation of service infomation for the EWV404. It worked well for my repair.
Text excerpt from page 7 (click to view)
Basics
Sensing System Theory - 5 cassette-fed and manual-fed paper. If the paper does not reach the top position of this sensor in the required time, the printer determines that a pick-up delay jam has occurred. Winding paper sensor PS303 detects the passage of paper from the photosensitive drum to the fuser. If the paper does not pass this sensor in time, the controller board determines that a jam condition exists. Paper delivery sensor PS301 detects the passage of paper through the fuser assembly. If the paper does not pass this sensor in time, the controller board determines that a jam condition exists.