I have a 2012 Speed Concept 9.9 with the Dura Ace DI2 7970 set up. I have the DA7971 TT bar shifters as well. The auto-trim and micro-shift features stopped working and I couldn't find any posts with fixes about this particular issue. I took my bike to my LBS and they determined that due to poor connections on the original installation, the harness had failed and needed to be replaced. I paid to have the harness replaced and all of the connections rewired and shrink wrapped. Within 100 miles the same issue presented again. I took it back to them and they determined that the shifting mode switch had stopped working because it got sweat and electrolyte mix on it. They said they cleaned it up and it started working again. Their solution was to wrap the shifting mode switch in a plastic baggie to protect it. Within 100 miles, the same problem has presented itself again. Has anyone seen this problem before or have any solutions? Thanks in advance!
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Re: Dura Ace DI2 autotrim/micro-shift issues [mrmruss]
[ In reply to ]
if it was just the micro-adjust that wasn't working I might believe the issue was somewhere in the wiring up front...but when you say the auto-trim wasn't working either, that moves the source of that particular problem away from the front end...on 7970 the brains of the system is in the front derailleur. that's what I'd plug into the diagnostic tool (SM-EC79) to see if it's working properly.
Carl Matson
Carl Matson
Re: Dura Ace DI2 autotrim/micro-shift issues [Carl]
[ In reply to ]
Carl, I really appreciate you taking the time to reply. I'll have them start there. I'll follow up when I have some results. Thanks again.
Re: Dura Ace DI2 autotrim/micro-shift issues [mrmruss]
[ In reply to ]
Hi, Is there any update on this issue? I have the same problem. No autotrim or microshift.
Re: Dura Ace DI2 autotrim/micro-shift issues [jyscott]
[ In reply to ]
On the old 7970 Di2 system, in the cable harness, one of the wires is coloured blue. That connection between front JB to FD to RD is the one that carries the position info from the RD to the FD that allows the auto trim, and also carries the micro adjust signal from the front JB to the RD. So, you should check the wiring harness for a nick or break that has affect the blue wire. They are really small wires, so if your LBS is not equipped, you will need to replace the harness.
See attached diagram:
http://forum.slowtwitch.com/...post=5407363#5407363
See attached diagram:
http://forum.slowtwitch.com/...post=5407363#5407363
Re: Dura Ace DI2 autotrim/micro-shift issues [goodboyr]
[ In reply to ]
Thank you. I'll have a look.
Re: Dura Ace DI2 autotrim/micro-shift issues [jyscott]
[ In reply to ]
So, I got a new wiring loom for it and it still has the same fault. Am I right to think it's probably an issue with the front derailleur?
Thanks for help..
Thanks for help..
Re: Dura Ace DI2 autotrim/micro-shift issues [jyscott]
[ In reply to ]
The only other item besides the wiring is perhaps a broken pin at the FD or rd. If you unplug the cables look at the socket on the FD and rd and see if there is a pin broken off. There should be 4 pins in each socket.
As well, the connect between the rear harness and the front jb is a bit tricky on the older system. It needs a very strong force to push together. I've had instances where it looked good but a harder push seated it and made the connection. There should be no gap between plug and socket at that connection.
As well, the connect between the rear harness and the front jb is a bit tricky on the older system. It needs a very strong force to push together. I've had instances where it looked good but a harder push seated it and made the connection. There should be no gap between plug and socket at that connection.
Re: Dura Ace DI2 autotrim/micro-shift issues [goodboyr]
[ In reply to ]
All pins present. Removed the front connection and reconnected; seems to be making a good firm click when I push it in.
I am going to take the FD up to my friend's tomorrow and plug it into his bike, see what happens.
I am going to take the FD up to my friend's tomorrow and plug it into his bike, see what happens.
Re: Dura Ace DI2 autotrim/micro-shift issues [jyscott]
[ In reply to ]
I'm in the Toronto area and I have the diagnostic unit for the 7970......in case you are nearby.
Re: Dura Ace DI2 autotrim/micro-shift issues [goodboyr]
[ In reply to ]
I'm probably a bit too far away; Scotland :-)
but, thanks for the very kind offer.
but, thanks for the very kind offer.
Re: Dura Ace DI2 autotrim/micro-shift issues [mrmruss]
[ In reply to ]
Dang that sucks.
I use barcons in friction mode -- so no meaningful help from me.
Want: 58cm Cervelo Soloist. PM me if you have one to sell
Vintage Cervelo: A Resource
I use barcons in friction mode -- so no meaningful help from me.
Want: 58cm Cervelo Soloist. PM me if you have one to sell
Vintage Cervelo: A Resource
Re: Dura Ace DI2 autotrim/micro-shift issues [jeremyb]
[ In reply to ]
FD worked fine on my friend's bike. Any ideas?
So far, all new wires and battery, it's not FD. Think I may have to get diagnostics box from somewhere.
So far, all new wires and battery, it's not FD. Think I may have to get diagnostics box from somewhere.
Re: Dura Ace DI2 autotrim/micro-shift issues [jyscott]
[ In reply to ]
Its got to be wiring. Can you take a picture of how the front plug and socket at the front jb looks when plugged in? I know you said that it made a click and went in, but I've had that happen and it can still go further in. Below is mine, which is fully in to compare:
Post deleted by jyscott
[ In reply to ]
Re: Dura Ace DI2 autotrim/micro-shift issues [goodboyr]
[ In reply to ]
Re: Dura Ace DI2 autotrim/micro-shift issues [jyscott]
[ In reply to ]
Yup. Looks perfect. So.much for that theory.
Re: Dura Ace DI2 autotrim/micro-shift issues [goodboyr]
[ In reply to ]
A friend is going to give me a right shifter and rear derailleur to try on it. That covers everything. If it doesn't work after that, I'm going to chuck it.
Re: Dura Ace DI2 autotrim/micro-shift issues [jyscott]
[ In reply to ]
I'd you are desperate, pm me and maybe we can arrange a loan of the diagnostic stuff.
Re: Dura Ace DI2 autotrim/micro-shift issues [goodboyr]
[ In reply to ]
Thanks again. I messaged a shop nearby and they are able to get a hold of the diagnostic kit. I will try the parts first, then take it to the shop if that fails.
Re: Dura Ace DI2 autotrim/micro-shift issues [jyscott]
[ In reply to ]
Update on this. I put my friend's rear derailleur on the bike and the system worked; microshift and auto-trim. So, it's a problem with the rear mech. Are these repairable or should I be looking to just replace?
Not repairable.
As a last resort, trying putting it in "reconnect mode". In a workstand, while pedaling, hold the adjust button down on the front jb. The rear derailleur will move through all the gears up and down. See if that works. If not, its on to eBay for you to find an rd.
As a last resort, trying putting it in "reconnect mode". In a workstand, while pedaling, hold the adjust button down on the front jb. The rear derailleur will move through all the gears up and down. See if that works. If not, its on to eBay for you to find an rd.