There’s nothing quite like the exhilaration of speeding along effortlessly and feeling the wind in your hair as you cruise around town on your silent eBike! It’s one of the few pleasures I get when I commute to and from work, or even if I’m running some of my more mundane daily errands. I will always recommend getting an electric bike due to its sheer usefulness and versatility.
However, every once in a while, something does go “kaput!” on the E-Bike, and I find myself having to pedal along like on a regular bicycle (shudder) or having to carry it to a repair shop… or trying to find a quick fix that I can handle myself.
No need to hit the panic button yet, I’m not a DIY expert either. But there are some specific things that you can try before resorting to the dreaded visit to the repair shop. Or at the very least you will be able to identify the source of the problem to get it resolved faster.
In this electric bike troubleshooting guide, I’ll help you identify and fix some of the more common problems to get you going again. Each “fix” is rated one wrench to five wrenches from easiest (i.e., no technical knowledge or tools required), to some basic DIY know-how (I’ll keep it simple, I promise) and up to the most challenging level (requiring specialised technicians and tools).
Electric Bike Troubleshooting Guide – Common Electric Bike Problems
The electric bikes’ problems will generally be confined to either the hub motor, the throttle, the power components, the battery pack (or battery charger), the pedal-assist system or error codes generated by the onboard computer. Whatever the case the repair needed will require some effort on your part, so be prepared.
Before we begin
Let me quickly cover the fundamental skill needed for anyone who owns an electric bike.
That skill is the removal of the rear wheel. While not recommended, there are many reasons that you might find yourself in need of removing the back wheel, such as:
- Tire replacement
- Hub motor repair
- Brake repair or replacement
- Calliper replacement
- Mudguard replacement
How to Remove Your Electric Bike’s Back Wheel
If you have a hub motor style E-Bike, you will have to disconnect all wiring (and you’ll probably have to cut and remove the zip ties holding them to the body).
Be sure to remember the locations of the zip ties so you can fix new ones on later. I highly recommend that you build up your E-Bike essential toolkit. It should include zip ties along with the usual basic items like a multi-tool, a mini pump, a tire patch kit, a roll of electrician’s tape, a spare inner tube and latex gloves (you’ll thank me for that last one).
If you’re lucky to have a centre drive motor, good news for you the rear wheel can be removed like on a regular bicycle. If not, then prepare to go through a series of steps to remove the tire.
In any case, you will need to turn your E-Bike over and rest it on the handlebars and seat (watch out for the display panel though). These instructions might differ slightly from model to model, but the sequence of steps is more or less standard:
- Not necessary, but a handy trick is to take a few close-up, clear photos of the rear wheel and hubs, etc. from both sides with your mobile phone. It will be a handy reference should you forget what goes where at some point.
- Engage the highest gear so that the chain is furthest away from the hub (after cutting off and removing the zip ties if there are any).
- Unplug the electric motor cable from both sides (it is located under the chain guard).
- Remove the rubber cover from the bolt holding the wheel to the frame and unscrew the two bolts holding the brake assembly in place.
- Remove the brake assembly and let it hang off to the side from its wires.
- Unscrew each of the bolts holding the wheel to the frame (one on each side) noting the positions and placements of the axle’s fit to the frame inset, in addition to the small washers on the wheel bolts.
- Gently remove the tire from the hub and lift the chain to unhook it from the chainring.
- You’re done.
- When it’s time to put the tire back on, use your mobile phone pictures as a reference to ensure that the washers, cables, etc. are all attached correctly.
So, with that out of the way, let’s look at some of the more common problems you might experience with your E-Bike.
Electric Bike Hub Motor Problems
Problem: Hub noise. Grinding, rattling, knocking or whining noise coming from the hub motor
Cause: It could be any of several issues which will, unfortunately, require that you open up the hub cover to inspect some of the components. Here are some likely Causes: Gear lubrication, loose components or bad ball-bearings:
Raise the electric bicycle on its kickstand, then remove the gear hub/motor cover. Rotate the back wheel and note where the sound is coming from.
If the sound is coming from the gears (they will require greasing), a loose magnet (it will need to be re-attached using epoxy) or a worn-out bearing (it will need to be replaced).
Controller issue: This is not a DIY repair, but at least you can tell which component is causing the problem. It is common to have the controller (also called the ECU), located inside the hub motor or the battery mounting cradle.
Consequently, this means that the controller is hidden from view for a sleeker and nicer cosmetic look to the electric bike. It is also more challenging to repair or replace a damaged controller when it is integrated this way. So, in this case, it has to be the repair shop, unfortunately.
E-Bike Throttle Problems
Problem: You have power, but throttle/motor not working.
Cause: It could be that the e-brake lever is engaged (which would prevent the motor or throttle from engaging), or is damaged. – Loose or damaged connection between the motor and controller.
Solution: Disconnect both plugs and inspect the pins for damage or pulled out pins (you might need to cut and remove a few zip ties to access the plugs). Reconnect and try again.
Cycle analyst problem: To verify if the cycle analyst is the problem, you can disconnect it temporarily. If the E-Bike works, you will need to have it inspected at a repair shop (please note that you should NOT operate your E-Bike with the cycle analyst disconnected as you might damage your battery).
Loose or damaged throttle connection: Throttles are usually quite reliable, but you can still check to be sure. The throttle connector has three pins with red, black and green on most models. Test the voltages on each pin and look for the following values: black to red 5V (approx.); black to green should give you variable readings between 1V and 5V as you engage the throttle.
The Electric Bike Won’t Turn On.
Problem: You cannot get your electric bike to power on.
Cause: It could be as simple as a loose or damaged battery plug or a more complex fault with the battery.
Solution: Loose or damaged battery plug: Is your battery plugged in? Yes, obvious but check anyway. Unplug the cable (could be red or black) and check to ensure that the metal tabs are intact. Reconnect and try again.
Battery drained below its safe operating level: Use a multi-meter to check the battery plug’s voltage. It should not be less than 40V for a 44V battery or less than 60V for a 66V battery (the battery specifications are usually printed on it or in the eBike’s user manual). If the voltage falls below the above values, then do not charge it and replace the battery immediately.
Damaged controller switch: Assuming that the battery is charged and OK, and is properly connected, then the culprit might be a faulty controller switch. Remove the screws (usually four screws) of the switch plate to access the switch for testing with a multi-meter. If the controller does not give an output reading between 4.3V and 5V to the throttle then the controller (or one of the parts connected to it such as the power switch or key switch, fuse, fuse holder, wires, or connectors) is faulty.
Why Does My Electric Bike Keep Cutting Out?
Problem: The E-Bike intermittently cuts out during use.
Cause: It could be as simple as a setting change in the cycle analyst, damage to the motor hall sensor or accidental pressing for the e-brake.
Accidental pressing of brake lever: Are you pressing the lever unintentionally while riding? This will cause the E-Bike’s motor to disengage.
Incorrect settings in the cycle analyst: Is your cycle analyst set up correctly, or could the settings have changed? Review the settings based on your owner manual.
Damaged brake lever or handlebar: In such as case, the motor inhibitor switch (which is basically a safety feature that cuts off the motor when you pull the brake lever) will be stuck in the “on” position.
Solution: Make sure the lever isn’t bent or damaged, and not in the engaged position. If the switch itself is damaged, it will need to be replaced (repair shop job). If you’re desperate and need a quick emergency fix, then you can disconnect the wires leading to the motor inhibitor (coming from the controller). This will resolve the issue… but it is not recommended. It will get you back on your way… but the bike has to go to the repair shop for a permanent fix.
Motor hall sensor might be damaged: Not a DIY job and will need to go to the repair shop for testing.
Electric Bike Batteries Explained
There are four types of batteries, and to understand the problem, we need to explain the basic differences. One is a lithium-ion (Li-Ion) battery another is a lithium polymer (LiPo) battery, the third is a nickel-metal hydride (Ni-MH) battery, and the last is a lead-acid battery.
The first two are the more commonly used ones in the UK and the US, while lead-acid batteries are more common in Asia. Li-Ion and LiPo batteries are much lighter than Ni-MH and lead-acid batteries as they hold charges better and for more cycles, can be recharged even if still not completely depleted. The downside of lithium-based batteries is that they have a life-span of 2 to 3 years (even without heavy use).
On an additional note, batteries can come in a hard or soft pack. Generally speaking, the hard pack battery is more durable and robust, but slightly heavier and has a 10% to 15% lower capacity than a soft pack battery. The disadvantage of soft pack batteries is that they are more fragile.
Always fully charge your battery the first few times. This will help your battery last longer, and it will calibrate best if you do this. Also, don’t start recharging immediately after a ride, allow the battery to cool down a bit first.
Here are some common problems and their Causes
Problem: Battery dead or not charging.
Cause: It could be a faulty battery or charger.
Battery pack not charging properly or is not fully charged: This is usually the result of storing your electric bike for a long period of time.
Solution: Try charging the battery pack for at least 8 hours and see if that resolves the issue. If not, then the battery will need to be replaced. A word of warning: do NOT charge your battery overnight unattended at home… it is not very common, but they can burst into flame.
Battery charger not working/does not charge the E-Bike
First thing you need to do is to make sure the charger is not defective by plugging it into an electrical outlet… if no indicator lights illuminate or blink, then the charger needs to be replaced. Otherwise, use the multi-meter to test the charger’s output voltage while plugged into the electrical outlet. If the reading is ZERO or if it is LESS than the voltage rating on the battery, then the charger is defective.
Faulty battery: As an addition to the first problem/Cause listing above, some people attempt to do a “rebuild” of their battery. My advice is: do not do it. However, for the die-hard DIY enthusiast, you can find instructions here.
Arguably the highlight of an electric bicycle, pedal-assist can give you anywhere from just 25% of power to your pedalling, up to 200%. There are almost no DIY Causes unless we’re talking about a loose wire or magnet.
Problem: Pedal assist is not engaging.
Cause: Issues that come up with pedal assist will usually involve the sensor, magnets getting dislocated or misaligned or an issue with the pedal-assist detector’s mounting.
Dislocated magnets: Check that the magnet ring is close enough to the pedal-assist sensor. Sometimes the magnet ring gets knocked out of alignment and starts to wobble.
Solution: You can adjust this with simple tools and be on your way quickly and easily. Just use your hands or a flathead screwdriver to push the disc closer to the bottom bracket sensor.
Pedal-assist detector mounted too far from disc: flip the E-Bike over and try bending the metal bracket holding the pedal-assist detector and check its alignment with the disc. Visually inspect the magnet ring for dirt or damage. The magnets on the ring should be clear and unobstructed to send a strong signal to the sensor.
- Trace the cable coming out of the PAS sensor to the connector.
- Cut and remove the zip ties to access the connector.
- Unplug the connector by pulling each side directly apart without twisting.
- Inspect the inside of the connector for dirt, damage, or moisture. If you find dirt or wet or damaged, then the sensor will need to be replaced.
Electric Bike Error Codes
Just like most digital devices, error codes will appear every once in a while. A full list isn’t possible here since this depends on the model, brand, etc.… but we can give you an idea of some of the main possibilities when you see an error. Again, note that the error codes themselves are not necessarily standard, so always refer to your owner manual.
Problem: In general, error codes warn you that something is wrong with your electric bike’s system. For example, when a sensor fails to calibrate correctly, when a connection is interrupted or when the software encounters an unexpected input are all reasons why you’ll see one of these codes.
Reboot the computer… I mean switching off the bike entirely and waiting for approximately 10 seconds and switching it on again. You’d be surprised the number of problems that can be resolved like this.
Open throttle fault (Error 04)
Throttle not resetting to its start position. Check for something blocking or preventing it from doing so (i.e. panel screen is twisted and activates the throttle or the thumb throttle is too close to the handle or panel screen and is pushing against it).
Throttle fault (Error 05)
Unplug the throttle cable and plug it back in. If the error does not disappear then the throttle may be damaged.
Low voltage protection (Error 06)
Battery voltage too low. Could be an incorrect type of battery for your eBike.
Overvoltage protection (Error 07)
Battery voltage is too high. Could be an incorrect type of battery for your eBike.
Motor hall signal fault (Error 08)
Sensor wires might be disconnected or damaged. Try disconnecting and reconnecting.
Motor phase line fault (Error 09)
A phase wire in the motor is either disconnected or damaged. Try disconnecting and reconnecting.
High-temperature fault (Error 10)
The controller has reached its maximum temperature. Just allow the electric bike to cool down before using it again.
Temperature sensor fault (Error 11)
The controller’s temperature sensor is disconnected.
Current sensor fault (Error 12)
The controller’s current sensor is disconnected or damaged.
Speed sensor fault (Error 21)
The speed sensor is disconnected or damaged.
Communication fault (Error 30)
The connection between the controller and the panel screen is disconnected or damaged.
Hopefully, using the information above, you have identified your problem and managed to fix it.
Failing that paying a visit to your local E-Bike repair shop will be your best course of action.