Had the parts store runa check engine diagnostic. Came back with Code EBM 08600, what does that mean?

That "code" doesn't make much sense in the world of OBDII diagnostics, which your vehicle uses. Your "parts store" is ill equipped to do anything of use for you, other than sell parts. You will either need to obtain a diagnostic tool that can retrieve proper OBDII codes and a shop manual to troubleshoot along with other necessary equipment, or you'll need to seek the guidance of a local shop near you to help diagnose your concern.