Bosch e-bike lost motor assist, display turned grey, no error codes - anyone seen this before?
Hi everyone,
I'm hoping someone has experienced something similar.
I have a Trek District+ 1 with a Bosch system.
Yesterday I had the crank arms replaced at a bike shop. After picking the bike up, everything worked perfectly. The motor assist was normal and I could change the assist level without any issues.
After riding for about 9 minutes, the motor suddenly stopped assisting. At the exact same moment, the display background turned grey, almost as if the system lost communication with something.
Since then:
- The display powers on normally.
- The battery level is shown correctly.
- The display still records things like elevation.
- Speed is stuck at 0 km/h, even while riding.
- I can't change the assist level with the + or - buttons.
- I also can't turn the lights on.
- There are no error messages on the display.
I took it back to the bike shop today. Three mechanics looked at it and connected it to the Bosch diagnostic software.
The strange part is that there are no fault codes at all. The diagnostics don't show any obvious problem, and the mechanics said they've never seen this happen before. They are now contacting Bosch and Trek for advice.
The speed sensor and spoke magnet both appear to be in the correct position, so it doesn't seem to be a simple sensor alignment issue.
Has anyone experienced anything similar? Could this be a faulty display, remote/controller, wiring harness, motor controller, or some kind of CAN bus communication issue that doesn't log an error?
Any ideas would be greatly appreciated.