I assumed you have a newer ACE based on your newer posts (welcome by the way), but I don't see what year your coach actually is. The other issue I did not mention in my previous post is that your chassis battery could just be bad.....new or old coach. It may not be taking a charge properly. A best first step would be to check all your batteries (12.6vDC typically represents a fully charged wet cell battery). Specific Gravity test each battery cell also to make sure water levels are up above the plates and readings are normal.
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