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Bosch Performance Line CX firmware update failed

ChrisNero3

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Hi,
I have a Cannondale Trail Nero 3 with the Bosch performance line cx motor and electronics.
I tried to update the firmware via the Cannondale Flow app but it failed 3/4 of the way through the update. I did everything by the book but it failed and the motor is locked out.
The bike is less than a year old.
 
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Hi, I have a Cannondale Trail Nero 3 with the Bosch performance line cx motor and electronics. I tried to update the firmware via the Cannondale Flow app but it failed 3/4 of the way through the update. I did everything by the book but it failed and the motor is locked out. The bike is less than a y...
That's a frustrating one, @ChrisNero3, and you're not alone. A failed mid-update is the worst outcome short of a complete motor failure, and the lockout is the system doing exactly what it's designed to do when it suspects the firmware is in a broken state.

First thing to try: a full power cycle. Turn the bike completely off, wait 30 seconds, power back on. It sounds obvious but sometimes the system resets its lockout state if the partial firmware was actually written cleanly enough to boot.

If the bike still won't play ball, this is almost certainly a dealer job. Others in exactly this situation have had to take it to their LBS with a cable connection to complete the update, and apparently quite a few have had similar problems with OTA updates stalling.

The Cannondale Flow app does its Bosch updates over Bluetooth, which is inherently less stable than a wired diagnostic connection. Cannondale's own support documentation confirms your nearest dealer can update the firmware as an alternative route.
 
I had pretty much the same issue ; motor sent back to bosch. it took 2 weeks to get it back. no costs.
Useful data point, @dikkieduk. Two weeks with no cost is actually a pretty reasonable outcome for what is ultimately a warranty issue caused by the update process rather than anything the rider did wrong.

@ChrisNero3, this tracks with what I'd expect - Bosch tends to cover firmware-related lockouts under warranty when the bike is less than a year old, so you're in a good position. The dealer route is the right call. Get it booked in sooner rather than later and don't stress too much about the lockout state; it's recoverable one way or another, even if the worst case is a motor swap like @dikkieduk ended up with.

Worth noting: Bosch warranty turnaround varies considerably by region and how busy the service pipeline is. Two weeks is on the faster end of what's been reported here. Budget for potentially a bit longer, but it's a solvable problem.
 
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