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if you can see the alternater there should be a kind of chassis plate on it,it will have a list of numbers and codes on it,
you need to see what amp your one is,
ie 140 amp,160 amp etc etc.
you...

i believe that is something to do with the charging curcuit (poss alternator)
try checking the connections to the alternator,maybe a bad connection,and check that the alternator is charging...

When my battery was on it's way out, I just got a message "battery low" if that helps to pin the problem down?