Modern E-bikes are designed to be problem-free. Of course they still need the standard bicycle maintenance you would expect. Like every electro-mechanical device, there may come the time where the electric-assist system just doesn’t wok right. This will be our subject in today’s article.
It should go without saying that the only way to know if it is having a problem, is to know how it normally works. So as you ride your E-bike, pay attention to how the controls and indicator lights operate during regular use. Your owner’s manual will go into this, and it is up to you to understand each of the controls and their functions. This will be part of the key to troubleshooting any problems you may encounter.
If trouble arises, make a mental or written note of each thing that seems different or wrong. Whether you attempt the repairs yourself or have a E-bike mechanic take care of it, the list of things you notice can be a road map to help solving the problem.
I do recommend having a qualified mechanic do the troubleshooting and repair. That is one of the big advantages of buying your E-bike from a local dealer. Not everyone is lucky enough to have an E-bike shop nearby, so you might have to dive into it yourself, or enlist the help of someone who is not 100% savvy on the repair.
The manufacture will do everything they can to help you over the phone or email, and they too will need an idea of the maladies. So make that list. If the bike is still under warrantee, they will ship out the needed parts free. They might suggest you send them the whole bike for the fix. In some ways this can be the best solution, but don’t expect them to pay for packing and shipping.
The electric-assist system consists of several parts. The motor, battery, charger, control unit, wiring harness, and all the input devices need to work as a team for correct operation. Each and every item needs to be correctly plugged in and functioning right. Your problem could be as simple as a loose wiring connection, or at its worst, a failed component. Our first goal before the repair, is to decide what to repair.
Before you start this process, remember that safety is the most important tool in your workshop. Keep your common sense in top gear and think before you leap. On the subject of thinking, it is so important to stay sharp during all your tests and repairs. Thinking can solve many problems that tools can’t. Don’t hurt yourself or make the problems worse. Please be careful and if you aren’t up to the task at hand, by all means, seek a professional. That said, let’s dive in.
Look for the obvious things first. Broken or loose wires can be visible, although sometimes they can be in a hidden spot. A battery that is not fully inserted or plugged in is a quick fix. A throttle unit that feels mechanically broken when you turn it should make you think that is the problem. A smell or excess heat from the control unit or motor is a tell-tale sign to suspect that component.
Next up is to evaluate your problem. Things like less battery range than normal can be a sign of a battery in need of replacement. More noise than normal will usually lead you to the motor. Certain things like braking, shifting and noise maladies are more than likely regular bike problems that have nothing to do with the electrical system. Chances are if you are reading this, your motor will not activate to give your bike an assist. That is the direction this post is now taking.
Ok, your motor will not run when it should, what should you do? You have already looked and felt for the obvious visible things and that hasn’t led you in the right direction. Let’s look at the source of power for your bike, the battery. Are your display or battery charge indicator lights coming on when you switch the power on? This will be our first needed clue. That could indicate a bad battery, connection or failed ECU (electronic control unit). You did recharge your battery, right? This sometimes overlooked chore could be the simplest of reasons you’re having problems.
Has it been charging like it always does? Are the charger lights working like you’re used to? 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’re good, let’s keep going.
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. I have had broken wires inside the battery case at the fuse holder on my E-Zip. I replaced it with a automatically resetting circuit breaker and have had no more problems. If the voltmeter won’t show the correct voltage, the battery is probably bad and in need of replacement. The problem could be with the charger instead. Best to replace them both as a team.
With lithium batteries, you don’t want to open the casing. If you have SLA (sealed lead acid) batteries, be aware of any fluid leakage they might have. Any sign of a leak is cause for immediate replacement. That fluid is caustic and needs to be cleaned correctly to prevent damage to your bike and battery holder case. That is one of the many reasons lithium batteries are the preferred unit for E-bikes.
Well, I’ve run out of space for today, so this will be a two part article. Stay tuned for the rest of the E-bike troubleshooting story. Thanks for checking in, Turbo Bob.
“When all else fails, read the instructions.”—Often said but rarely followed. I DO think it is a good idea.