8100 Di2 Stopped Working
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8100 Di2 Stopped Working
I’m helping a friend troubleshoot his bike. His 8100 groupset stopped responding to shifting inputs on the levers. He is able to connect to all the components and has updated all the firmware. E Tube recognizes all the Di2 components. When he runs the RD through crash mode recovery, it runs through all the positions, so it’s clearly still functional.
Given that all the components are recognized and up-to-date, I suspect this is some oddball software issue. He has checked all the connections though, of course, the fact that all the components are recognizing would seem to be a good indication that everything is properly connected.
Battery is fully charged.
Any help on next steps would be appreciated.
Given that all the components are recognized and up-to-date, I suspect this is some oddball software issue. He has checked all the connections though, of course, the fact that all the components are recognizing would seem to be a good indication that everything is properly connected.
Battery is fully charged.
Any help on next steps would be appreciated.
#2
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Do both Brifters fail to shift?
Barry
Barry
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Thanks, Justonwo for posting this.
Yes, I'm the fellow with the dead DI2. I headed out for a ride and nearly ran a stop light and stopped quickly. I was still in the big chain ring. So, as I've done on a number of occasions, I hopped off, shifted my bike into the small chain ring, and gave the pedals/crank a spin. The bike shifted perfectly into the small chain ring. Alas, the DI2 then died. In my attempt to revive the DI2, I did everything that Justonwo reported.
And, yes, both derailleurs are dead.
Yes, I'm the fellow with the dead DI2. I headed out for a ride and nearly ran a stop light and stopped quickly. I was still in the big chain ring. So, as I've done on a number of occasions, I hopped off, shifted my bike into the small chain ring, and gave the pedals/crank a spin. The bike shifted perfectly into the small chain ring. Alas, the DI2 then died. In my attempt to revive the DI2, I did everything that Justonwo reported.
And, yes, both derailleurs are dead.

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I recently saw a few local riders reporting a dead Di2 battery. One of them had the battery revive sometime after finishing the ride in one gear -- both front and rear derailleurs didn't work, like you had. Then it failed again on a ride a few days later. I think the battery itself has control circuits for the system, so I see how it could still hold a charge, but the Di2 wouldn't work. The rider has a replacement battery now, and so far it's fine on the first few rides.
My 6850 Di2 never has had this problem, and I've never heard of these failures until this month. Perhaps there's a batch of Di2 batteries a few years old that are intermittently failing.
~~~
As a side note, when I replaced my Di2 battery after 5 years or so (it was starting to need a charge every 200-300 miles), I didn't plug in the cable completely. There's a slight click as the cable is plugged in, but press harder to get the second click! Now it's got a connection. (That took a while to troubleshoot!)
My 6850 Di2 never has had this problem, and I've never heard of these failures until this month. Perhaps there's a batch of Di2 batteries a few years old that are intermittently failing.
~~~
As a side note, when I replaced my Di2 battery after 5 years or so (it was starting to need a charge every 200-300 miles), I didn't plug in the cable completely. There's a slight click as the cable is plugged in, but press harder to get the second click! Now it's got a connection. (That took a while to troubleshoot!)
Last edited by rm -rf; 09-12-22 at 07:21 PM.
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Unlike 12sp Di2, R8100 still functions when on charge.
1. Place Di2 in charge using a USB brick that can supply more than 1A (iPhone brick won't work)
2. Do you see a red light on the SM-BCR2 charger?
3. Wait 10-15mins do the Brifters work?
4. Will the light on the charger go out if left on charge?
5. Do the Brifters work?
You mentioned Firmware has been updated, Are you using Bluetooth or a hard wired interface?
If hardwired, which interface do you have?
Barry
1. Place Di2 in charge using a USB brick that can supply more than 1A (iPhone brick won't work)
2. Do you see a red light on the SM-BCR2 charger?
3. Wait 10-15mins do the Brifters work?
4. Will the light on the charger go out if left on charge?
5. Do the Brifters work?
You mentioned Firmware has been updated, Are you using Bluetooth or a hard wired interface?
If hardwired, which interface do you have?
Barry
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Unlike 12sp Di2, R8100 still functions when on charge.
1. Place Di2 in charge using a USB brick that can supply more than 1A (iPhone brick won't work)
2. Do you see a red light on the SM-BCR2 charger?
3. Wait 10-15mins do the Brifters work?
4. Will the light on the charger go out if left on charge?
5. Do the Brifters work?
You mentioned Firmware has been updated, Are you using Bluetooth or a hard wired interface?
If hardwired, which interface do you have?
Barry
1. Place Di2 in charge using a USB brick that can supply more than 1A (iPhone brick won't work)
2. Do you see a red light on the SM-BCR2 charger?
3. Wait 10-15mins do the Brifters work?
4. Will the light on the charger go out if left on charge?
5. Do the Brifters work?
You mentioned Firmware has been updated, Are you using Bluetooth or a hard wired interface?
If hardwired, which interface do you have?
Barry
I updated the firmware via the DI2 charging interface that came with my bike.
I've tried using shifting the bike while it's charging. Alas, that doesn't work.
Thanks, again.
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I recently saw a few local riders reporting a dead Di2 battery. One of them had the battery revive sometime after finishing the ride in one gear -- both front and rear derailleurs didn't work, like you had. Then it failed again on a ride a few days later. I think the battery itself has control circuits for the system, so I see how it could still hold a charge, but the Di2 wouldn't work. The rider has a replacement battery now, and so far it's fine on the first few rides.
My 6850 Di2 never has had this problem, and I've never heard of these failures until this month. Perhaps there's a batch of Di2 batteries a few years old that are intermittently failing.
~~~
As a side note, when I replaced my Di2 battery after 5 years or so (it was starting to need a charge every 200-300 miles), I didn't plug in the cable completely. There's a slight click as the cable is plugged in, but press harder to get the second click! Now it's got a connection. (That took a while to troubleshoot!)
My 6850 Di2 never has had this problem, and I've never heard of these failures until this month. Perhaps there's a batch of Di2 batteries a few years old that are intermittently failing.
~~~
As a side note, when I replaced my Di2 battery after 5 years or so (it was starting to need a charge every 200-300 miles), I didn't plug in the cable completely. There's a slight click as the cable is plugged in, but press harder to get the second click! Now it's got a connection. (That took a while to troubleshoot!)
My battery isn't dead. It's fully charged and shifts the rear derailleur through the cassette (and back) when I engage crash recovery mode.
#10
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Last time I saw this, it was a d-fly causing the issue.
i re-flashed all the components with current firmware and it was fixed.
I don’t believe you can do that with the charger.
are you East Bay? I sent you a PM but realized you can’t yet reply. Can you at least read them?
Barry
i re-flashed all the components with current firmware and it was fixed.
I don’t believe you can do that with the charger.
are you East Bay? I sent you a PM but realized you can’t yet reply. Can you at least read them?
Barry
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Last time I saw this, it was a d-fly causing the issue.
i re-flashed all the components with current firmware and it was fixed.
I don’t believe you can do that with the charger.
are you East Bay? I sent you a PM but realized you can’t yet reply. Can you at least read them?
Barry
i re-flashed all the components with current firmware and it was fixed.
I don’t believe you can do that with the charger.
are you East Bay? I sent you a PM but realized you can’t yet reply. Can you at least read them?
Barry
Thanks for the PM but, yeah, I can't yet access it.
I tried restoring the system with D-fly removed. I'll try again.
Thanks so much!
John
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John,
your buddy PM’ed me. You are a bit too far away!
The charger PC interface can’t always recover a bricked Di2 system.
You might have to find a store or friendly local with a SM-PCE02
All the best
Barry
your buddy PM’ed me. You are a bit too far away!
The charger PC interface can’t always recover a bricked Di2 system.
You might have to find a store or friendly local with a SM-PCE02
All the best
Barry
Last edited by Barry2; 09-13-22 at 09:30 AM.
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Thanks, again, to all who chimed in on this thread and especially to my buddy Juston for starting it for me.
I return to report a successful revival of my Ultegra DI2!
As best my LBS could tell, I most probably popped a wire loose when I picked my bike up, spun the crank to shift from the big to the small chain ring, and then let the bike plop back onto the road.
By unplugging and replugging all of the wire connections, I'd fixed that. Then, though, I needed to update the firmware to reboot the system.
And here, Barry, you were absolutely right: my SM-BCR2 charger PC interface couldn't recover my bricked Di2 system. The LBS had a fancier gizmo that did the trick.
Again, thanks to all.
I return to report a successful revival of my Ultegra DI2!
As best my LBS could tell, I most probably popped a wire loose when I picked my bike up, spun the crank to shift from the big to the small chain ring, and then let the bike plop back onto the road.
By unplugging and replugging all of the wire connections, I'd fixed that. Then, though, I needed to update the firmware to reboot the system.
And here, Barry, you were absolutely right: my SM-BCR2 charger PC interface couldn't recover my bricked Di2 system. The LBS had a fancier gizmo that did the trick.
Again, thanks to all.
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Remember.....
Everybody needs a buddy with the "fancier gizmo"!!
And the buddy with the "fancier gizmo" needs a six-pack of IPA !

Barry
Everybody needs a buddy with the "fancier gizmo"!!
And the buddy with the "fancier gizmo" needs a six-pack of IPA !

Barry
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You're a man after my own heart! As always, I added a $20 tip to my bill, to go toward the shop's beer fund (it really has one).
Thanks again for posting such great information.
John
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Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or whole biked 57,58)
Life is too short not to ride the best bike you have, as much as you can
(looking for Torpado Super light frame/fork or whole biked 57,58)
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Very kind of you to offer to help. I may buy the 12 speed pro interface for my own use. I realized me overpriced LBS charged me $60 to update the firmware on my new 9200 install.
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The fancier gizmo (FG) is currently one size fits all.
10,11, & 12 speeds.
However you do need to cobble together the connectors for the 12sp.
One thing to note, you no longer connect to the Charging Port on the bike.
It goes into the Di2 wiring.
I pop-off the Di2 wire from the RD and then connect the FG between the RD and it's Di2 wire.
OH and after you've been sitting there for a while wondering why your 12sp Brifters wont flash for luv nor money...
The first flash on the Brifters can't be done wirelessly. You connect the FG to each Brifter directly.
Yes there is a Di2 connector under the rubber cover. Future firmware updates can then be completed wirelessly with the FG connected to the bike.
Barry
10,11, & 12 speeds.
However you do need to cobble together the connectors for the 12sp.
One thing to note, you no longer connect to the Charging Port on the bike.
It goes into the Di2 wiring.
I pop-off the Di2 wire from the RD and then connect the FG between the RD and it's Di2 wire.
OH and after you've been sitting there for a while wondering why your 12sp Brifters wont flash for luv nor money...
The first flash on the Brifters can't be done wirelessly. You connect the FG to each Brifter directly.
Yes there is a Di2 connector under the rubber cover. Future firmware updates can then be completed wirelessly with the FG connected to the bike.
Barry
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The fancier gizmo (FG) is currently one size fits all.
10,11, & 12 speeds.
However you do need to cobble together the connectors for the 12sp.
One thing to note, you no longer connect to the Charging Port on the bike.
It goes into the Di2 wiring.
I pop-off the Di2 wire from the RD and then connect the FG between the RD and it's Di2 wire.
OH and after you've been sitting there for a while wondering why your 12sp Brifters wont flash for luv nor money...
The first flash on the Brifters can't be done wirelessly. You connect the FG to each Brifter directly.
Yes there is a Di2 connector under the rubber cover. Future firmware updates can then be completed wirelessly with the FG connected to the bike.
Barry
10,11, & 12 speeds.
However you do need to cobble together the connectors for the 12sp.
One thing to note, you no longer connect to the Charging Port on the bike.
It goes into the Di2 wiring.
I pop-off the Di2 wire from the RD and then connect the FG between the RD and it's Di2 wire.
OH and after you've been sitting there for a while wondering why your 12sp Brifters wont flash for luv nor money...
The first flash on the Brifters can't be done wirelessly. You connect the FG to each Brifter directly.
Yes there is a Di2 connector under the rubber cover. Future firmware updates can then be completed wirelessly with the FG connected to the bike.
Barry
I have SRAM AXS on my gravel/bikepacking bike (as Salsa Cutthroat). SRAM software is as precise as Shimano shifting. Alas, SRAM shifting is as imprecise as Shimano software.
#21
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Connecting the SM-PCE2 Di2 interface
justonwo
There are two types of E-Tube Di2 wiring
10 & 11 speed (Large plug) SD50
12 speed (Small plug) SD300
Items required
For Connection to 10 & 11 sp
SM-PCE2 interface (USB for PC) Comes with an Interface to SD50 wire. The interface connector is a weird 2 pin connector. Come on Shimano, if it was also SD50 that would have been better.
You need either a spare Di2 port on the bike, Some under stem charging junctions have 5 ports.
or
A SD50 type 4 port junction and an additional SD50 wire.
For Connection to 12 speed
SM-PCE2 Interface
EW-AD305 Di2 Conversion Adaptor It's a two port SD50 to SD300 converter.
SD300 wire
Either a free Di2 port on the bike (Battery does have 3 ports) Assuming Disc brakes there will be a free port, but you likely have to pull the seat post out. (Brifter port does not count as a free port on Disc brake bikes.)
or
SD300 type 4 port junction and another SD300 wire.
With 12 speed rim brake bikes, the brifters are NOT wireless, they are wired. They also have additional Di2 ports on the brifters. I can't comment on if these might qualify as free ports.
But hey.... those a RIM brakes, so who cares!
Lastly, I've seen rumor of a replacement Interface cable that is SD300 (Y79M9801T). Not only was I unable to find one, upon thinking about it, I decided it was a bad idea.
The tiny two pin socket on the interface seems a little fragile. I'd rather just leave the supplied SD50 cable connected and not swap cables.
Barry
There are two types of E-Tube Di2 wiring
10 & 11 speed (Large plug) SD50
12 speed (Small plug) SD300
Items required
For Connection to 10 & 11 sp
SM-PCE2 interface (USB for PC) Comes with an Interface to SD50 wire. The interface connector is a weird 2 pin connector. Come on Shimano, if it was also SD50 that would have been better.
You need either a spare Di2 port on the bike, Some under stem charging junctions have 5 ports.
or
A SD50 type 4 port junction and an additional SD50 wire.
For Connection to 12 speed
SM-PCE2 Interface
EW-AD305 Di2 Conversion Adaptor It's a two port SD50 to SD300 converter.
SD300 wire
Either a free Di2 port on the bike (Battery does have 3 ports) Assuming Disc brakes there will be a free port, but you likely have to pull the seat post out. (Brifter port does not count as a free port on Disc brake bikes.)
or
SD300 type 4 port junction and another SD300 wire.
With 12 speed rim brake bikes, the brifters are NOT wireless, they are wired. They also have additional Di2 ports on the brifters. I can't comment on if these might qualify as free ports.
But hey.... those a RIM brakes, so who cares!

Lastly, I've seen rumor of a replacement Interface cable that is SD300 (Y79M9801T). Not only was I unable to find one, upon thinking about it, I decided it was a bad idea.
The tiny two pin socket on the interface seems a little fragile. I'd rather just leave the supplied SD50 cable connected and not swap cables.
Barry
Last edited by Barry2; 09-16-22 at 10:31 AM.
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#23
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Producing hardware (mechanical or electronic) and producing software are very different processes. The latter is a far less mature engineering discipline, and the resulting process also typically has far more ways to fail.
An analogy that relates software to a mechanical system: every line of code in a software product is the equivalent of a moving part. And they all have to work perfectly, every time, for the system to function as desired reliably.
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justonwo
There are two types of E-Tube Di2 wiring
10 & 11 speed (Large plug) SD50
12 speed (Small plug) SD300
Items required
For Connection to 10 & 11 sp
SM-PCE2 interface (USB for PC) Comes with an Interface to SD50 wire. The interface connector is a weird 2 pin connector. Come on Shimano, if it was also SD50 that would have been better.
You need either a spare Di2 port on the bike, Some under stem charging junctions have 5 ports.
or
A SD50 type 4 port junction and an additional SD50 wire.
For Connection to 12 speed
SM-PCE2 Interface
EW-AD305 Di2 Conversion Adaptor It's a two port SD50 to SD300 converter.
SD300 wire
Either a free Di2 port on the bike (Battery does have 3 ports) Assuming Disc brakes there will be a free port, but you likely have to pull the seat post out. (Brifter port does not count as a free port on Disc brake bikes.)
or
SD300 type 4 port junction and another SD300 wire.
With 12 speed rim brake bikes, the brifters are NOT wireless, they are wired. They also have additional Di2 ports on the brifters. I can't comment on if these might qualify as free ports.
But hey.... those a RIM brakes, so who cares!
Lastly, I've seen rumor of a replacement Interface cable that is SD300 (Y79M9801T). Not only was I unable to find one, upon thinking about it, I decided it was a bad idea.
The tiny two pin socket on the interface seems a little fragile. I'd rather just leave the supplied SD50 cable connected and not swap cables.
Barry
There are two types of E-Tube Di2 wiring
10 & 11 speed (Large plug) SD50
12 speed (Small plug) SD300
Items required
For Connection to 10 & 11 sp
SM-PCE2 interface (USB for PC) Comes with an Interface to SD50 wire. The interface connector is a weird 2 pin connector. Come on Shimano, if it was also SD50 that would have been better.
You need either a spare Di2 port on the bike, Some under stem charging junctions have 5 ports.
or
A SD50 type 4 port junction and an additional SD50 wire.
For Connection to 12 speed
SM-PCE2 Interface
EW-AD305 Di2 Conversion Adaptor It's a two port SD50 to SD300 converter.
SD300 wire
Either a free Di2 port on the bike (Battery does have 3 ports) Assuming Disc brakes there will be a free port, but you likely have to pull the seat post out. (Brifter port does not count as a free port on Disc brake bikes.)
or
SD300 type 4 port junction and another SD300 wire.
With 12 speed rim brake bikes, the brifters are NOT wireless, they are wired. They also have additional Di2 ports on the brifters. I can't comment on if these might qualify as free ports.
But hey.... those a RIM brakes, so who cares!

Lastly, I've seen rumor of a replacement Interface cable that is SD300 (Y79M9801T). Not only was I unable to find one, upon thinking about it, I decided it was a bad idea.
The tiny two pin socket on the interface seems a little fragile. I'd rather just leave the supplied SD50 cable connected and not swap cables.
Barry