[KSagal]

Yes. There are two batteries, so there are two lights.

They should be green which means the segway is happy with the batteries fitting its expectation. Solid green means charging, blinking green is that they are topping off, or trickle charging. But always 2 LEDs.

The front LED indicates the front battery, the rear LED the rear battery.

If there is only one green, and one red LED at a particular time, it means one good battery and one bad battery at that moment. IF the red LED goes out, and does not turn to green, it means that for some reason, the segway has given up on trying to charge that battery.

Your segway will not start up with only one good battery.

Sometimes, the problem is not really the battery, but is the connection, or that you want to reset the segway. You can do this by replacing both batteries, or swapping them.

Before you do this, be sure you know where the green LED is, and where the red LED is. IF you swap the batteries front to back, and the red LED follows, then it makes sense that the battery indicated by red LED is bad, or at least something is wrong with it. It does not mean it will never work again, but it does mean that you need to do something more than wait for the segway to correct the problem, as that will not happen.

I do not recall as I have never seen it, but I think the segway gives an error code if the battery is there, and it knows it is bad. I am not sure about this however.

I do know that you will not ever be able to start the segway if it thinks one of the batteries is bad.

By the way, many times people think the segway has been plugged in when it really was not. In this case, most often the rear battery will go dead, and then too dead for the segway itself to revive it. IF your rear battery is giving the red or no LED then it most likely spent a significant amount of time not being plugged in to active current, regardless of what you were told.

Good luck. Keep us posted.