Thank you for responding quickly this morning. This is a predator. Never did see anything of an error message. Are you referring to something like "no communication with ECM"? Or along those lines? I initially plugged it in to clear a code for a glow plug that we replaced, then preceded to load the 100hp tune. It stored the original back up then tried the tune but it said unable to tune vehicle- or something to that affect. Look forward to your input. Thank you.