When I recently tried to charge my nicon I couldn't get the red light to come on. The charger green light was on but no red. I checked the voltage in the v3i and it read 8.03 volts. I check all connections, etc. and thought I had a battery issue or a failed charger. After a few hours I unplugged the charger and saw a button on the face of the plug. One push and it was reset and ready to charge. Everyone may already know of this reset button but I wanted to post a message just in case someone doesn't.