Ok, we've determined they are 12VDC batteries. Now how did you "test" them to determine they were at 5VDC? Did you use a meter? If so, are you familiar with the meter? Have you checked them with a hydrometer? Assuming you are correct with your finding of 5VDC then the batteries are most likely done. Next will be battery size. Somewhere on either battery or both they will be a size i.e. 31, 27 etc. That will determine how many CCA are needed for your coach if you don't have the manual and assuming someone has not changed them. Since you have no information in your profile and you haven't told us what kind of coach you have it's difficult to offer any more info. Please provide Coach name, model, year and make. Someone who has a similar coach can help you tremendously. Good luck...keep posting....Dennis