Bosch error 504: cause and fix
Error code 504 is the most common message on tuned Bosch bikes of generations 1 to 4. Here is what is behind it and how to get rid of it, based on the shop’s information.
What does error 504 mean?
Message 504 means the Bosch system has detected an inconsistency in the speed signal. Bosch responds by heavily limiting motor support.
When does the error appear?
- With hardware chips that alter the spoke magnet signal, the message is well known.
- With the software upgrade via license code it is rare, according to the shop. In individual cases a detection can kick in above approx. 32 km/h and briefly limit support.
How to reset it
- Connect the bike to your computer via Micro-USB or USB-C, just like for the activation.
- Open the activation link from your order email (Chrome or Edge, Windows or macOS).
- Reset the state with the web tool.
After that the motor works normally again. If anything is unclear, the shop’s support helps.
Does this also affect the Bosch Smart System?
No. Error 504 affects the classic Bosch systems of generations 1 to 4 with displays such as Intuvia, Kiox, Nyon or Purion. The Smart System has a different typical pitfall: the bike still only goes 25 km/h after the upgrade because a limited riding profile is active in the eBike Flow app. More in our guide Bosch Smart System: 30 or 45 km/h.
Which system do you have?
A round or oval charging port and the eBike Connect app mean classic system (Gen 1–4). A square plug and the eBike Flow app mean Smart System. The full overview is in our guide Which system do I have?
The Bosch Gen 1–4 upgrade in brief
- Motor support up to approx. 50 km/h, depending on system and tyres
- Activation via Micro-USB or USB-C in the browser in about 5 minutes, no chip
- reversible at any time
- Afterwards the display shows half the speed (25 km/h on the display equals 50 km/h). A GPS app is useful to check, see Display after tuning.