The Crown WAVs are the best designed. I have this problem periodically and usually when the operators leave them charging overnight. I have a charger at home that works with AGM batteries as well. I just hook it up to two of the 6V batteries on one side and turn on the fast charge for about 30 secs, then turn on the key switch.
Yes, always use AGM batteries in WAVs, but Interstate has AGM batteries that will work with WAVs we always buy and over $400 less for a set over Crown's.
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