Why Electric Bike Lights Not Working?

Lights on an electric bike are essential accessories to get. It’s a must if you want to see the road clearly in the low light or to be seen in daylight. However, lights come with various types of setup.

Most of them are integrated with the bike controller, where very few are portable. Besides, the dynamo-powered headlight is a thing nowadays.

Due to this diversity, it is difficult to get a fix when the ebike lights are not working. That’s why I have come up with the blog.

Here I will talk about a fix applicable for all types of ebike light setup. Read the post until the end to precisely get a solution to light failure.

7 Common Reasons electric bike lights not working

Electric bike lights can stop working because of loose connections, dead batteries, or damaged wiring. A broken dynamo motor or corrupted microprocessor can also cause this problem. Besides, the bulb itself can get fused and stop lighting.

Why Electric Bike Lights Not Working

However, I’ve made it simple with bullets. Now, identify the problem(s) by checking the possibilities below.

  1. Dead battery: If the light is portable or not integrated with the ebike circuit, it can stop working due to a dead battery.
  1. Loose connections: As an electric bike has many wiring, there are chances of loose connections or disconnections. For this reason, the electric bike light can stop functioning.
  1. Damaged wiring: Like the previous problem, damaged wiring can also cause an incomplete circuit. Thus, the bike light stops functioning.
  1. Faulty switch: If the above problem doesn’t exist, your ebike light may have a faulty on-off switch. Of course! The ebike light won’t turn on if the switch is not working.
  1. Loose microcontroller: A microcontroller operates the electric bike light in an integrated setup. So, when the microcontroller is corrupted or loose, the light won’t work.
  1. Broken dynamo motor: Dynamo-powered light gets illuminated while the motor is rotating. When the motor is broken, it can’t transfer the energy into light. Thus, the electric bike light stops working.
  1. Fused bulb: Sometimes the problem is light there, but you can’t see it. If your electric bike lights are subjected to overheating or overload, the bulb can get fused. So, the bike light can stop functioning for fused bulbs.

A quick fix to faulty electric bike lights

A quick fix to faulty electric bike lights

Most of the time, the electric bike light gets fixed after a quick fix. So, you should give it a try before even considering the repair job. However, follow the below tips for a quick fix.

  1. Replace the battery: When the light battery is dead, you must recharge or replace it. If you have a non-rechargeable battery, it’s better to switch to a rechargeable one than replace it. For that, get a Rechargeable Battery Pack. It’s easy to set up and provides a long-time backup. So, you must give it a shot.
  1. Rectify electrical faults: You must focus on the electrical problems after solving the battery problem. Check the connections, battery prongs, and wiring. Reconnect any disconnection or loose connection you find. Then set the battery prongs back if it is bent or causing disconnections. Finally, replace the wiring if it is damaged from the inside.

How to repair electric bike lights

If the electric bike light doesn’t get fixed after a quick fix, you should go for advanced troubleshooting. For that, you will need the below tools and supplies.

  1. Allen Wrench
  2. Screwdriver Set
  3. Soldering Iron
  4. Small Needle Nose Plier

Tip-1: Change fused bulbs

A bike light with filament can be easy to replace. Just get a Filament Bulb, remove the old one, and set the new one. But changing the LEDs is a bit tricky. But you can do it by following the below steps. So get some High Power LEDs and do the repair job yourself.

  1. Open the light: While repairing, it’s good to bring the light off the bike. For that, loosen the mount. If it is not adjustable, use an Allen wrench to loosen it. Then open the light with a screwdriver.
  1. Remove the LEDs: After opening the light, remove the LEDs. For that, separate the light board first. Then remove the bulbs with a small needle nose plier. Do it carefully, or you can break the board.
  1. Install the new bulbs: You have removed the exhausted bulbs. Now, install the new bulbs. Set the bulbs in the right combination and fix it with soldering.
  1. Close the light: After you are all done, close the light and remount it.

Tip-2: Adjust switch & controller

The electric bike light switch & controller can get repaired with minor adjustments. You have learned how to open and close the light. When doing it, check the switch and microcontroller. If the controller is loose, place it in the correct place. If it is still not working, you have to change it. For that, get a suitable Microcontroller and replace the old one.

However, do the same with the Switch Button. Get a new one if it is not working.

Tip-3: Swap the whole light

How to repair electric bike lights

If the lights have too many problems, it’s not worth repairing. In this case, you better get a new one. However, there are many factors to consider while getting a bike light. The most important factors are explained below.

  1. LED or filament bulb: LEDs are way better than filament bulbs. It’s more efficient and long-lasting. Besides, heat loss is minimum here.
  1. Lumen or lux: Lumen refers to the brightness of light where lux indicates its intensity. Higher lumen will provide you a brighter light. But higher lux can cover more area for illuminating.
  1. Beam pattern: It influences the lux count. The wider beam offers higher lux, and the narrower beam provides lower lux. If you are a fast rider, you will need a light with higher lux.
  1. Lighting mode: Besides illuminating the road, bike lights have other purposes too. Communicating with other riders is one of them. For that, it should have at least 2 or 3 lighting modes.
  1. Visibility: The rear blinker should be visible both at night and in daylight. For that, it should have at least 50 lumens of brightness.
  1. Batteries: Lithium-ion batteries are best for ebike lights. But internal battery system or separate power pack is the factor to consider. The integrated battery is useful for short commutes as it occupies less space. A portable power pack is suitable for tours and bikepacking. Because you can carry extra batteries while riding long distances.
  1. Charging system: The USB charging system is best for a bike light. It’s convenient and fast.
  1. Waterproofing: It’s good if the bike light an IPX5 rating. IPX7 is best. But it should have at least an IPX5 rating to save it from raindrops and dust.

Anyways, considering the above factors, NiteRider Lumina is the best headlight, in my opinion. If you ask about taillights, check out Cygolite Hotrod. I promise it won’t let you down.

Freaky Tips: Things can get complicated if you try to fix the light with an integrated setup. So, if you don’t have enough knowledge or confidence to work on it, bring it to an electric bike shop. They can help you in this case.

Frequently asked questions about electric bike lights

How do you use a bike light?

Bike lights can be used to be seen or see the road. It’s good to have a pair of lights; one is a headlight, another is a taillight. A headlight can help you see the road at night or at low light. Taillights are used to increase your visibility on the road.

Should I use bike lights during the day?

Yes, of course. If you ask me about the rear light or taillight, it’s necessary for both day and night. You will need at least one taillight to be seen on the road precisely.

You may think about the headlight that it is useful only at night. But in reality, it’s proved to useful at day too. How? Just think about a day with bad weather and low light. You will get the answer.

Why do bicycle lights flash?

You may have seen bike lights flashing, especially the taillights. Well, it has many reasons. The first thing is that it can help you to communicate with the traffic. Another reason is that it can save some battery.

But the most important thing is that it attracts the traffic more to increase your visibility.


Before getting a solution, you must understand the problem well. Same for the ebike lights. If you don’t know why the ebike lights were not working, you can’t repair them. So, I have explained it before giving a solution on repair work. I hope you have read it by now.

Anyways, the repair work can need some tools and supplies. I suggested the best options for them. You can check them out. I hope your ebike light is working well by now. Keep illuminating your ride.