BBSHD firmware failure

moutchz

New Member
Region
Canada
BBSHD still runs but no software/display can read or write controller anymore – possible UART/firmware corruption?

I’m trying to diagnose a weird BBSHD issue and I’m running out of ideas.

The motor still powers on and the bike runs normally, but I can no longer communicate with the controller through ANY software or display-based tuning method.

What happened:

  • I was modifying settings on the BBSHD
  • Afterward, communication with the controller stopped working
  • Since then, no tool can properly read/write the controller
What I already tested:

  • Multiple programming attempts
  • Different software:
    • Bafang Config Tool
    • Speeed app
    • EggRider
    • other tuning/config apps
  • Different USB ports/computers
  • Tried disconnecting peripherals
  • Bike still runs normally
  • Display still powers on
  • Motor still functions
Important details:

  • EggRider also cannot read/write the controller
  • Programming cable also cannot read/write the controller
  • This makes me think it’s not just a display issue
  • No permanent error codes on display
  • Controller is responsive enough to operate the motor normally
Things I’m trying to determine:

  1. Does this sound more like:
    • corrupted firmware/EEPROM
    • damaged UART communication section
    • partially bricked MCU
    • something else?
  2. Is there an actual recoverable stock BBSHD firmware available anywhere?
    • not config files, actual firmware
  3. Has anyone recovered a controller in this exact state using:
    • STC ISP
    • Daniel Nilsson firmware tools
    • bootloader recovery
    • UART reflashing?
  4. If both EggRider and programming cable fail to communicate, does that strongly point toward hardware failure?
At this point I’m mainly trying to determine whether this controller is realistically recoverable or whether I’m wasting time chasing firmware files.

Any help from people who’ve actually recovered a “runs normally but unreadable” BBSHD would be hugely appreciated.
 
Have you tried a new 1T4 cable?
If so, might be easier to just replace the controller, about $150 USD
Flashing the firmware probably requires special tools that might not be end user available and more expensive if tracked down anyway.
Though I believe the Bafang BESST CANbus tool has UART communication capabilities.
And if ends up being a hardware issue, it still won't fix it.
 
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See endless_sphere.com for a thread covering firmware updating; however, I'm with Gioni. NEW controller!
 
I'm with you @tomjasz and wanted nothing to do with CANBUS.

I had to spend an extra $100 to get the UART version of the BBS02B before it went extinct.
 
A few months ago, I unplugged the BBS02 C961 display to check some program settings, I noticed the pins were bent in the IT4 cable. Unplugged the battery so I could straighten them, but forgot about the charged capacitors. Kapow! In hindsight, should have unplugged the IT4 or used a plastic tool, but the damage was done. Dead controller.

Bought a new uart controller from China for about $100, with no apparent tariff charges. Everything was fine, but the old throttle had blown out too, Had to replace it too.
 
A few months ago, I unplugged the BBS02 C961 display to check some program settings,

A few months ago I bought a BBS02B with a P860C display, and a programming cable (from the beauty outdoor store. Lol)


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I noticed the pins were bent in the IT4 cable. Unplugged the battery so I could straighten them, but forgot about the charged capacitors. Kapow!


I do know about the capacitors in the controller.
My Voltbike came with a built-in real time clock.
I figured out that the clock in the display ran off those capacitors to keep time for months.

If I push the power button on the display with the battery removed, the display would do its start up routine, then shut down.
Then the clock in my display would forget what time it was.


In hindsight, should have unplugged the IT4 or used a plastic tool, but the damage was done. Dead controller.

Bought a new uart controller from China for about $100, with no apparent tariff charges. Everything was fine,

So, your talking about a controller that's inside the motor housing right?

Is it a difficult job to replace?

I've had the plastic cover/gear housing off the the motor to grease it up, but that's as far as I got.

but the old throttle had blown out too, Had to replace it too.


I gots throttles coming out the yin yang. Lol
 
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