Bosch error 0x591001: Drive unit authentication error
The drive unit could not be identified correctly during the system handshake. As a result, motor support is switched off or comes in delayed, and walk assist is unavailable. The bike can still be pedalled without power, but no assistance is delivered until the fault clears.
| Drive system | Bosch eBike (DiagnosticTool / eBike Flow hex code) |
| Severity | Dealer needed |
| Keep riding? | Do not keep riding |
| Typical cost | Dealer diagnostic fees typically run EUR 30 to 80, software updates are usually bundled into that fee, and a drive unit replacement outside warranty is commonly EUR 600 to 1200 depending on the motor model. |
Likely causes
- Recent software update left the drive unit and display on mismatched firmware versions.
- Dirty or oxidised contacts between the battery and the frame mount breaking the data link.
- Loose or corroded connector between the drive unit and the battery or display harness.
- Battery not seated fully so the authentication handshake fails on start-up.
- Aftermarket or swapped drive unit that has not been paired to the original system.
- Internal electronics fault inside the drive unit preventing the ID reply.
- Corroded or water-damaged wiring from rain washing or pressure washing.
How to fix Bosch error 0x591001
- 1. Connect the bike to the eBike Flow app and run any available system software update before riding.
- 2. Switch the system fully off using the display or power button.
- 3. Remove the battery from the frame and inspect the contacts for dirt, oxidation or moisture; clean if needed.
- 4. Refit the battery, making sure it clicks and locks fully into the mount.
- 5. Switch the system back on and check whether the code clears on a short test ride.
- 6. Repeat the off, remove, refit and restart sequence once more if the code reappears.
- 7. Book the bike in at a Bosch dealer for diagnostic readout if the code persists after these steps.
Warranty: A genuine authentication or drive unit fault within the first two years and with proof of purchase is normally covered by Bosch as a component defect; water ingress, crash damage and modifications are excluded.
Typical cost: Dealer diagnostic fees typically run EUR 30 to 80, software updates are usually bundled into that fee, and a drive unit replacement outside warranty is commonly EUR 600 to 1200 depending on the motor model.
Frequently asked
Can I reset bosch error 0x591001?
Yes, by switching the system off, removing and refitting the battery, then restarting once any pending software update is installed. If the code returns straight away the reset has not cleared the fault and the bike needs dealer diagnostics.
Is it safe to keep riding with this error?
No, because motor support is off or delayed and walk assist is unavailable, which makes hill starts and pushing the bike harder. The bicycle can still be pedalled without assistance, but the fault should be cleared before relying on it again.
How much will the repair cost and is it covered by warranty?
Diagnostic work is typically EUR 30 to 80 and a drive unit replacement outside warranty runs EUR 600 to 1200 depending on the model. Within two years of purchase a genuine component fault is normally covered by Bosch warranty, excluding water damage and crash damage.
Related Bosch codes
Manuals and video
- Bosch eBike Help Center: official error-code index
- Bosch eBike downloads: quick start guides and battery guide
- Bosch eBike dealer search (DiagnosticTool readout)
Official source: www.ridewill.com
Not an official Bosch document. Compiled from workshop experience and public service information; details can differ per system version and bike brand.