battery power cutting off while going down road

ok.my first problem was that i discovered my ground wire to the starting battery was loose and i twisted it to get ready to tighten it up.the terminal end broke in half in my hand.at that point i grabbed hold of the positive cable to check it and it was very hot.i guess that is because i ran for a while with a bad ground connection!so,i replaced both terminal ends and checked voltage on both batteries...house and starting and both were good...12.2 and 12.4....coach will start and run now but every once in a while,service engine light will flash once and acts like transmission slips and coach acts like it loses power.drove coach the previous day about a 30 minute trip and had none of these issues...any ideas on what might be causing my problems?