Like has been said, check battery water level. The inverter was an option, make sure you have one, don't know what model you have, but on mine the inverter is in a bay between the batteries and the electrical bay. also the remote control is next to the surge guard display. Now, while your on battery power only, turn on some over head lights, these or also 12 volt, then turn on you pump do the lights dim out or stay almost full bright, if they stay up, then you have a different problem. You can also monitor your battery voltage from the remote on inverter. Make sure the battery charger on the inverter is turned on. Mine did not charge the chassis batteries from the inverter and the house batteries do not charge from the alternator. You'll need one of these for that.
http://www.ebay.com/itm/Bi-directional- ... hi&vxp=mtr
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