Updated for E-Tube for Windows Version 4.0.2
As of October 13 it is possible to do basic component firmware recovery using the SM-BCR2 charger. This doesn't mean the SM-PCE1 and SM-PCE02 are now obsolete and you'll never need to visit the bike shop again, but it definitely is a step in the right direction.
I originally intended to record an E-Tube V4 version of the video that's further down this page and use the SM-PCE02 to recover my component, but things turned out even better. This time I didn't have any components that required updating, but seeing as E-Tube Project V4 offers the firmware rewrite functionality I used that to run the firmware update process and yanked out the USB cable at 30%.
Naturally E-Tube Project complained that the firmware rewrite failed and that my component would require recovery. I then reconnected the SM-BCR2 charger and E-Tube project offered to recover the firmware. I let it do its thing and the ST-6870 was indeed recovered - without having to use the SM-PCE02!
Note that this does not mean you can recover every 'bricked' component using the SM-BCR2. Do not try this at home.
Updating Di2 firmware is a relatively easy process. It usually can be done at home using the SM-BCR2 charger. However, this process can fail and when it does, your component is “bricked” and it stops functioning.
The SM-PCE02 / SM-PCE1 and tools
So what is the SM-PCE02? It’s a PC Linkage Device, but unlike the SM-BCR2 charger it will not charge your bikes. Most consumers will therefore not own an SM-PCE02, but your local bike shop most likely has one.
It doesn’t charge the bike, but it can do a lot more in terms of diagnostics and recovery. These units can:
- Run battery drain diagnostics (SM-PCE02 only)
- Check each component for errors
- Connect to a single component or the entire bike
- Recover and re-write component firmware
That last part is what we’re interested in here, so let’s get to work.
There’s a video too!
Don’t feel like reading this page? That’s OK – there is a video too. It shows the entire process, from bricking the component to eventually fixing it. The video is just over 10 minutes long.
First – corrupt some firmware
There wouldn’t be much to restore without a component that is severely confused. Unfortunately I don’t have a box of Di2 components that need fixing in the garage (I wish), so let’s try to “break” a component first.
I happened to have this set of ST-R8070 shift levers that I bought recently – they’re meant to go on my Bowman Palace 3. One of these levers I updated a while ago, but the other was still as outdated as they get. My plan was to update this shift lever and disconnect the cable halfway through the update process…. so that’s what I did!
Unfortunately the E-Tube firmware update progress indicator is just that – an indicator. I unplugged the component with 15 seconds left to update and E-Tube Project told me I should plug the SM-BCR2 back in and let it finish. I didn’t and closed E-Tube Project instead.
When I restarted the application and connected to the bike it told me nothing was wrong. Not only was the shift lever firmware not corrupt at all, it had also updated it to the latest version.
I now only had one component left that I could update and break – the FD-R8050 front derailleur. I decided to update this and disconnect the component as soon as the progress bar appeared.
E-Tube Project offered to restore the unit, but I would not let it – the goal here is to restore firmware using the SM-PCE02, not using the SM-BCR2 charger. It then displayed a red box next to the front derailleur and when I disconnected / reconnected the bike the component disappeared completely.
Restore the component firmware
Now that we have a component that is so confused that it does not show up in the list of installed components, let’s try to fix that.
I will follow the same steps your local bike shops do when restoring Di2 firmware. If you want to try this at home you need:
- An SM-PCE02 or the older SM-PCE1
- The TL-EW02 tool to make your life easier
- A component with its firmware corrupted
- Single-unit connection manual (not required, but useful)
Restoring component firmware happens in “single unit connection mode”. Basically you connect only one component to the SM-PCE02, instead of plugging in the entire bike. This way you can be 100% sure you’re not writing front derailleur firmware to a rear derailleur (or any other component).
Using single unit connection mode is simple: you just use the button on the top right – the one with the E-Tube wire on it.
It will then immediately display the ‘Connection check‘ screen. This makes sense, because there isn’t much else you’d want to use single unit connection mode for.
Those ‘Back‘ and ‘Cancel‘ buttons both take you back to the previous screen, so I clicked ‘Next‘. E-Tube Project will now attempt to recognize the connected unit:
The FD-R8050 front derailleur‘s firmware was definitely destroyed beyond repair. It could not even tell E-Tube what kind of device it was.. E-Tube just says “Unit is not recognized“.
You then click ‘Next‘ and E-Tube will once again try to identify the component.
In this case it failed again. This is normal when the firmware is no longer in any recognizable state, there is nothing to worry about.
Now.. if you click ‘Next‘ it will overwrite the current firmware with the correct one – even though the component was not recognized it can still be restored.
How you ask? Each piece of Di2 hardware has a bit of code that identifies what it is. This information is not part of the firmware and should always be intact.
E-Tube uses this information to identify the component and restore its firmware.
E-Tube has just written new firmware to the component. Note that it still says “unknown unit” on the right, but the box has turned green and the message on the left shows us it has been successful.
Click ‘Next‘ and it will once again try to identify the component, this time using the information from the newly written firmware.
I have to admit I did not click ‘No‘ to see what would happen, but I imagine it’d go back to the previous page and try rewriting the firmware again.
Now at this point you could probably quit E-Tube Project if you wanted to, but you really should stick around for these last steps.
E-Tube Project will guide you through the error check for this component, making sure it is indeed fully functional.
The error checking procedure involves it shifting the derailleur a couple of times, so E-Tube Project asks you to turn the cranks while it performs the diagnostics.
Also, don’t put your fingers between the chain and chain ring…
After the check has completed E-Tube reports “a fault could not be found“. Click ‘Ok‘.
E-Tube once again confirms that the front derailleur functions normally.
The ‘Cancel‘ and ‘Next‘ buttons both lead eventually lead to the ‘Connection Check‘ screen:
At this point I could have quit E-Tube Project using either ‘Back‘ or ‘Next‘, but I made it run the ‘Connection check‘ again. It now correctly identifies the front derailleur:
Clicking the ‘Update firmware‘ button displays this windows, indicating that it has written the latest firmware to the front derailleur.
That’s it, you can now run the ‘Error check‘ again, or ‘Rewrite firmware‘ if you really want to. There isn’t any reason to do that, so let’s exit the application.
Click ‘Complete Setup‘ to return to the Connection check screen. You can now close E-Tube Project.
All done! Want your own SM-PCE02?
Now that’s all – the front derailleur is fully functional again. In case you’re interested in buying an SM-PCE02, keep these things in mind:
It will not charge your bike
Get a spare Junction B / E-Tube wire
If your PCE does not come with a Junction B and extra E-Tube wire, consider getting one. These units plug into an E-Tube port, meaning that you’ll probably have to disconnect something from your Junction A in order to connect the SM-PCE02.
Also, a 600-1000mm Electric Wire will allow you to bypass any ‘suspect’ wires, helping you to troubleshoot battery drain issues.
Use these links to support the site
If you’re shopping at Amazon or Ebay, consider using the links below to support the site. If you make any purchase you’ll earn the site a small commission, at no cost to you:
- SM-PCE02: eBay
- TL-EW02 Plug tool: Amazon | eBay
- SM-JC41 Junction B: Amazon | eBay | Wiggle
- EW-SD50 Electric Wire: Amazon | eBay | Wiggle
Get in touch
Missing something? Or are things unclear? Just get in touch and I’ll do my best to help you.