Brose eBike – Most common error codes and how to fix them

Brose is a manufacturer with many years of experience in the automotive industry, and its motors feature a self-diagnostic system that can detect faults and display its own error codes on the display (on bikes without a display, this information is shown on the LED lights on the battery).

These codes are part of the self-diagnostic system and help identify whether the problem originates from the battery, motor (Drive Unit), display, or peripherals.

If you are interested in the mechanics and common faults of these Brose motors, you can visit this article:

Which bicycle brands use Brose motors?

It should be noted that Brose is a manufacturer of motors and bicycle systems, but it also allows other manufacturers to use its motors with their own systems, such as displays, batteries, etc. Decathlon uses Brose motors with its own displays on many bicycles.

On the other hand, we have the manufacturer Specialized, which for years has used Brose motors in its bicycles under its own name—Specialized Turbo (Specialized Turbo SL motors are usually from another manufacturer, Mahle)—and with its own batteries and displays. Although the motors are physically similar, the programming, electronics, and some small details in the construction of the motors may differ.

There are also other manufacturers such as BMZ (https://www.bmz-group.com/) that offer integration of their components and batteries with Brose motors. Bicycles that use the BMZ system include Bulls, Rotwild, and others.

Although error codes are often shared, it should be noted that different manufacturers may have different descriptions or their own errors. In this article, you will find a guide to the most common errors in Brose systems, their causes, and what to do to fix them.

How to fix Brose motor error codes?

In many cases, simply restarting the bike (switching it off, waiting a few seconds, and switching it back on) is sufficient.

You should also check all the connections between the different components of the electrical system – motor, display, control panel, battery. In many cases, you may find rust or bent pins, which can easily solve problems that appear to be very serious.

If the problem persists, you can check the list of quick fixes provided by the manufacturer Brose, but in many cases it is time to take the bike to a workshop that has the diagnostic systems of BMZ, Specialised, and Brose, so that a more thorough diagnosis can be made.

One method recommended by many manufacturers of electric bicycle systems is to replace components—changing the control unit, display, battery, etc.—until the fault is found. At BiciFix, we have several bicycle models so that we can test components to ensure they are in good working order. These parts and this method have already helped us repair more than 100 Brose motors with various faults from different manufacturers.

List of Brose/BMZ motor error codes, with descriptions and solutions:

In the list below, you can see that in many cases the solution is to replace the engine (drive unit). Do not worry, many of these faults can be repaired at specialist engine repair workshops.

Para ver los códigos de errores de bicicletas Specialized, visita Guia de los motores Specialized Turbo

Código	Componente	Descripción	Solución rápida
10 / 12	Battery	Low voltage/battery discharged (12 is critical)	Charge with original charger. If the problem persists, replace the battery.
11	Battery	Overvoltage detected	Restart. If the problem persists, replace the battery.
20	Motor	Internal electrical failure	Restart. If the problem persists → replace the drive unit.
21 / 23	Motor	Error in temperature sensor	Restart. If the problem persists → replace the drive unit.
24	Motor	Undervoltage (possible short circuit or damaged peripherals)	Check peripherals (display, lights), connectors, and wiring. If the problem persists → replace unit.
26	Motor	Intermittent electrical failures	Check battery cable and contacts. Do not disconnect battery with system switched on. If problem persists → replace components (cable → battery → motor).
31	Motor / Lights	Overcurrent in the light system	Check lights and wiring. Disconnect or replace faulty lights. Restart. If the problem persists → replace unit.
44	Motor	Overheating	Allow to cool. Reduce assistance/load. Restart.
46	Motor	Motor blocked	Restart. Check chain, chainring. If the problem persists, proceed with further diagnostic (replace the motor unit).
60 / 85	Display	Communication error between display and motor	Check wiring. Try another display. If the problem persists, proceed with further diagnostic (replace the motor unit).
70 / 72 / 73 / 91–93	Motor	Errors in torque sensor	Restart. If the problem persists, proceed with further diagnostic (replace the motor unit).
71 / 75	Motor	Cadence sensor errors	Restart. If the problem persists, proceed with further diagnostic (replace the motor unit).
76	Display	Cadence sensor errors	Check or replace display. Restart.
81	Motor	Undetected speed signal	Check magnet and speed sensor. Adjust position and wiring. Restart.
82 / 83	Motor	Software error	Restart. If the problem persists, proceed with further diagnostic (replace the motor unit).
90 / 74	Motor	Serious system error	Restart. If the problem persists, proceed with further diagnostic (replace the motor unit).
95	Lights/ Brake	Overcurrent in the brake light	Check and replace brake light. Restart.

Some preventive recomendations

• Always use original bike chargers. If the charger has broken, do not attempt bad repairs, the investment in an original charger is always recommended (even though the chargers are indeed quite expensive).
• Don’t disconnect the battery with the system on – it tends to cause some intermittent errors.
• Check regularly cables, conectors, and lights. When working on the bike, be carefull with the cables and connectors – they are small, and when internally routed can be easily damaged. Use cable grease sprays to improve the connections and the fit of the connectors when working on them.
• Avoid installing high-powered, not approved lights or peripherals that can overload the system.
• Perform annual preventive maintenance: cleaning of the connectors, cleaning and re-greasing of the bearing protections rins, and if the engine is already more than 3-5 years old, a complete maintenance of the engine.
• Install upgraded protection X-rings under the crankarms: https://bicifix.net/product/crank-seal-upgrade-for-brose-motors/

What can do if the error persists?

En BiciFix (Gandía) ofrecemos:

Unfortunately, many of the errors cannot be related directly to a mecanical error – some can indeed be caused by mecanical failures, but they will also be seen and felt in the behaviour of the motor itself – for example a broken belt that is impeding the movement of the motor could generate an error code, but you will already know that there is a problem with the motor. If you decide to change the belt, you can find original Brose Drive belts and tools to change it in our online shop:

If you live near our physical shop in Gandia, Valencia, you can also bring your bike for repair and diagnostic. In BiciFix Gandia, we perform repairs of Brose motors on daily basis.

• Diagnostic and repais of Brose motors

Frequently Asked Questions

Can I continue using the bike with an error on the display?

We don’t recommend it. Brose components are not cheap, and we recommend cutting your ride short and solving the error first, before amouting repairs that can get expensive.

Are the errors easily solved ?Unfortunately, no

Unfortunately, not all of them. If it is a disconnected or cut cable (as if very often the case), it is easy enough to repair it, but if it is an electronic fault in the display, or motor controller, the diagnostic can be quite difficult.

Are the codes in all Brose engines (Alu, Mag, S, T) the same?
Most of them do, although there are small differences between generations and integrations in different bicycles.