I found this manual and I believe page 2-1 shows the cable referred to by JayVee. Access may not be easy for replacement.
http://www.intercycle.com/media/wysiwyg/haendlerzone/yamaha/Yamaha_X94_Manual.pdf
http://www.intercycle.com/media/wysiwyg/haendlerzone/yamaha/Yamaha_X94_Manual.pdf