Thank you for the explanation Alfa Wheels. I will try again with the sport switch once I have charged the batteries and see if that makes any difference.
My model does not have reverse.
As for the Indicator plug, from your explanation does that mean I can just hook up this voltmeter to monitor battery voltage?

https://www.amazon.com/GEREE-Waterproof-Voltmeter-15-120V-Voltage/dp/B01CFNTLUO/ref=sr_1_1?ie=UTF8&qid=1523176334&sr=8-1&keywords=mini+Current+Voltage+Tester+48v
My model does not have reverse.
As for the Indicator plug, from your explanation does that mean I can just hook up this voltmeter to monitor battery voltage?

https://www.amazon.com/GEREE-Waterproof-Voltmeter-15-120V-Voltage/dp/B01CFNTLUO/ref=sr_1_1?ie=UTF8&qid=1523176334&sr=8-1&keywords=mini+Current+Voltage+Tester+48v