that is a bad sign. you are having data issues. either from a loose data cable. but more possibly a blown head. i'd give you some pointers about a data swap that would diagnose if it is your slider board or head. but, i don't think i want blood on my hands if you do the swap wrong and fry your printer.
at least recheck your cables and make sure all the ends are clean with no fraying or bent ends, and that they are plugged in firmly. turn off your machine on front, switch off on back, unplug, and press the front power button four times before doing any poking around in the head carriage. and try to keep one hand on the platen if possible.