Many E-bike batteries have a fuse built-in to them that is accessible from the outside. The fuse can fail, just because, but normally if it does, there is a problem with the battery or wiring. The fuse is there to protect your battery and bike from an overload of power that can cause intense heat or fire. A simple voltmeter test can give you a general idea if the battery is holding juice and if the fuse is bad. Most batteries should read about 2-3 volts more than their ratting on the voltmeter. 24, 36, and 48 volt systems are the most common. You will need to know which you have before you proceed.

Some batteries have two wires or connectors where the reading can be taken. Some have more, and that can be the beginning of your confusion. Those extra connections are to feed info about the battery cell condition and balance to the computer, or battery temperature information. They won’t give you the readings you need. If voltmeter tests already sound like more than you understand, you are going to need some help and this post won’t be enough to guide you. So take your list of noted problems and search for a E-bike expert. If you found a bad fuse, replace it with the same exact item and try again. If it blows out again, I would suspect a shorted battery or bad wiring inside the case.