Electric Yamaha prob

[CPORTER]

Hello , I'm have a issue i hoped you guys could help me with . When you plug the charger in it clicks and lights up the abnormal light.As for the cart its self , When you turn the key on, it starts to move then stops and the battery gauge read zero likes theres no power .I lift the seat and switch to tow mode and the power gauge reads full then when i hit the brake it makes a buzzing noise when that stops i switch it back to run mode it starts to move then makes a clicking noise then the cycle starts again . I checked with a volt meter and the batterys showed 8.6 per battery . It drove great last season , and was stored properly.Any ideas Thanks