just installed a new Batterie and it won't charge.

I bout my Mac book Pro 15" Retina in late 2013. I had it built with upgrades in the graphic and memory cards for my job. The batter would not stay charged long and one fan did not work. I bought the battery kit from Ifixit and fans. I followed a video step by step to take out and install the new battery and fans. When The Charger never turned green and I cloud not turn it on I went through the step again to make sure I did not miss anything. Still will not charge. I noticed the charger box never got hot so I bought a new charger today hoping that is the problem. If that is not the problem which I don't think it is because the light is on what else could it be? Thanks Linda