We receive many calls at our shop from people who can not get their battery chargers to work on dead batteries. Here is the scoop. Battery chargers have a logic circuit that determines the voltage of the battery before turning on. In the case of an E-Z-GO Powerwise charger, the logic board is actually powered by the DC voltage from the golf car. If there is no voltage in the batteries, the logic board does not even activate. In a normal situation, the logic board gets its current from the cart through the small red wire in the DC power cord. That current powers up the board and the board determines if the voltage is within a certain range. On a 36 volt syastem, that range is somewhere between about 30 volts adn 39 volts. When the charger sees voltage in that range, it closes a relay and sends power to the transformer which sends a DC current to the golf cart. When the charge reaches certain parameters, the relay opens and the charge is complete. In the case of the Powerwise charger, the charger will NOT restart by itself if the plug is left in the cart. In order to restart the charger, you need to unplug the DC cord from the cart plug it in agan, restarting the process. If the batteries are dead and the charger won't start there is a way to get it started. You will need to charge the batteries with a 12 Volt automotive battery charger. Charge them 2 at a time in "Series" for 30 minutes or so. This will bring the cart voltage into range to start the charger.