Why Bosch eBike Battery not Charging

The battery is one of the essential components of e-bikes. So, when it’s not charging, you won’t get the expected facility from the electric bike. However, Bosch is one of the best electric bike brands.  But, even the best has flaws. This is what is happening with you. The battery is not charging on your bike.

Anyways, charging problems can occur either for the charger or battery. Either it happens accidentally, or within the time being, you must solve it to keep riding. Before that, you must figure out the reasons behind the problem. So, let’s not continue the suspense and learn everything about it.

Why Bosch e-bike battery not charging

Why Bosch eBike Battery not Charging

A Bosch e-bike battery can stop charging due to the charger error. Also, it happens when the battery management system (BMS) prevents charging the battery for safety issues. Besides, it can occur if the battery itself is exhausted.

This information is difficult to understand if you know little about it. Don’t worry. Let me make it easy for you. Here are the reasons why Bosch eBike batteries stop charging.

  1. Damaged charger: A charger can get damaged in many ways. But it happens only for one reason which is a “sudden shock.” However, a charger gets shocked due to a short circuit, overheating, or overflow of electricity. Besides, it occurs because of thunderstorms while charging. After a shock, the charger gets damaged inside. Thus, the battery stops charging in Bosch ebike.
  1. Safety circuit: Modern electric bikes like Bosch feature a safe battery management system (BMS). These BMS have integrated safety circuits. It helps the battery prevent overload while charging. However, most Bosch ebike batteries come with a 5V input. So, the battery stops charging when the charger’s output is over 5V. This is how Bosch ebike battery stops charging because of the safety circuit.
  1. Electrical faults: Minor electrical faults also can stop the charger from functioning. Sometimes the BMS, the charger, and everything is okay. Still, the battery doesn’t get charged. It happens when there are loose connections or disconnection on the charging jack or wiring.
  1. Exhausted battery: Sometimes, the battery itself refuses to get charged. It happens when the battery is exhausted. When the battery charge or discharge, chemical reactions occurs inside. But the chemical inside the battery gets contaminated day by day. Gradually, these chemicals stop reacting to each other for being corrupted. Thus, the bosch ebike battery stops charging within the time being.

A quick fix to charging problems in Bosch e-bike battery

Before troubleshooting the ebike, you should try a quick fix. Sometimes, the problem gets solved by this. Here are two steps to a quick fix.

  1. Reset the battery: You have already learned that charging gets stopped because of the safety circuit. In this process, the circuit gets broken in BMS. However, you can reconnect the circuit by resetting the battery. Resetting the battery in the Bosch ebike is easy. Just press and hold the BMS reset button for 10 seconds. The battery will be reset.
  1. Rectify electrical faults: Minor electrical faults can be rectified quickly. That’s why I have included it in the quick fix. However, you can reconnect the disconnections by soldering. So, get a Soldering Iron Kit and keep fixing the charger.

How to troubleshoot Bosch e-bike battery not charging Issue

troubleshoot Bosch e-bike battery not charging

The electric bike should get fixed after a quick fix. Otherwise, you have to try another charger. If the battery is charging with that charger, buy a New Bosch Charger for your bike. If the battery is exhausted, get a new Electric Bike Battery and replace the old one. Here is the step-by-step process to replace the Bosch ebike battery.

  1. Firstly, unlock the battery box and remove it from the bike frame. If there is a screw system, loosen it with a Screwdriver. Now disconnect the connectors, and the box will separate from the bike.
  1. Secondly, unscrew the lid under the box and bring the old battery out. Before that, cut the wiring from the battery. Sometimes, the battery is attached with adhesive. Remove the adhesive with a knife. The battery will come out easily.
  1. Thirdly, install the new battery. For that, reconnect the battery with the connectors.  Before that, change connectors if they are damaged severely. You can reapply the adhesive to ensure the battery’s stability inside the box.
  1. Lastly, set the battery box to its place. Close the lids and put the box on the mount. Then, tighten the screws, and you are all set.

How to prevent charging error on bosch ebike

I hope you have got the solution to charging problems. You should be understood by now that this problem can cost you a lot to some extent. So, it’s better to prevent this situation than fix it again. Here are some tips on how to avoid charging errors on Bosch e-bikes.

  1. Optimal load: Check the source and charger while charging the battery. You should be careful about the input and output voltage of the charger. Make sure there is no overload on the charger or battery. Keep the voltage at an optimal level. Thus, you can protect the charger or battery and keep charging your ebike.
  1. Avoid short circuits: To protect the charger/battery, you must prevent overheating, overloading, and short circuits. For that, you keep some things in your mind. Firstly, don’t charge your ebike in extreme weather like thunderstorms. Besides, don’t charge it over time. Of course, there is no problem in charging the battery overnight. But there is still a risk of short circuits. So, it’s better to avoid charging overnight.

Frequently asked questions about Bosch e-bike charging

Why are bosch ebike battery lights flashing?

Bosch e-bike battery lights flash for the same reasons the battery stops charging. It’s all about a faulty charger or an exhausted battery. So resetting the battery can fix this problem. Otherwise, you will need to replace the battery.

How do you check a Bosch e-bike battery?

You can simply get a Digital Multimeter, connect it and measure the voltage, current, or resistance. Thus you can test a Bosch ebike battery. For example, you want to know if the battery is exhausted or not. For that, measure the voltage. If the battery is exhausted, there will be zero or very low voltage.

How long will a Bosch eBike battery last?

Unlike other electric bikes, Bosch comes with a durable battery pack. Bosch claims that the available batteries can roughly provide 1500+ charging cycles. The average mileage is from 50 to 60 in Bosch e-bikes. That means you can ride from 75000 to 90000 miles with a single bosch e-bike battery in a lifetime.

Should I charge my Bosch eBike after every ride?

There is no such rule. But it’s good to charge the bosch ebike after every ride. Thus, the bike will be ready whenever you go for the next ride. Besides, lithium-ion batteries need frequent charging. Otherwise, the chemical inside the battery will start drying. So, you should charge the battery after every ride.


A battery without charge has no use. So, an electric bike with a chargeless battery doesn’t remain “electric.” You can’t enjoy actual electric biking experiences if the battery is not charging. So, you must solve this problem to keep riding the electric bike.

However, I have described the problem precisely in this post. Besides, its solution is also suggested. So, you can completely get rid of charging errors by following this post.

I hope your ride will never stop again.


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