Outer Limits 4x4 Board

i installed a electronic battery isolator and a second battery last week and four days later the wife went to drive up the road at night time and she said everything just died! i checked everything and the only thing i found was that the negative terminal on the second battery was loose! i disconected the isolator and jumped started the main battery as the secondry battery was good! could the fact that the terminal was loose have drained all the power from the main?

hi is the alternator charging? or the main battery may be on the way out. this is assuming the isolator is working correctly is it ok now?

with only the main batery conected it runs fine and starts ok again!