Login required to started new threads
Login required to post replies
Got a used set of di2 7970. Hooked everything up and am able to shift the front derailleur. But not able to shift rear derailleur. If I put junction A box into adjustment mode, I can hear some ticking emitting from the rear derailleur when I press upshift and downshift but still it will not shift. If this is an indication that the rear derailleur is in crash mode, how do I reboot it? Or is it toast and I need to purchase another rear derailleur.
thanks in advance for the advice.
Holding the junction box button longer should reset the derailleur if it has been bumped into safe mode. I think it is supposed to beep on reset.
There was a 7970 Di2 testing unit available for first gen Di2. You could check your area for a LBS that still has one around that can be used to check your system. Di2 harness wire failures are probably more common than derailleur failures.
If it's not working at all you might have a chance to get it checked with that tool. Mine was working from time to time and then the tool is worthless. DA have a 3 year warranty, I got the RD replaced but I'm the first owner. Don't know if you have luck that way. Get the tech support hotline from your LBS and call to send the RD in.
-shoki
I have the testing unit. Are you in Canada?
I bought a new junction b assembly. When pressing junction a button 5 sec or longer, I do not hear any beep. After unplugging the battery / replugging the battery / unplugging the rear dérailleur / plugging the rear dérailleur. I was able to get the rear dérailleur to perform its reset but afterwards still no response from shifters
Yup. There is no beep. However, by your symptoms now, I would check the connections to your rear shifter. See if the battery check works from the rear shifter by holding one of the shifting buttons on it. If the battery check light illuminates, you know you have a good connection to the shifter. Those plugs at the shifter require a solid click in. Sometimes, either due to a crash or change in position on the handlebars, the shifter will unplug, if there is no slack in the cable leading to it. You may have to unwrap the bars to get to the connection at the shifter.
If you know someone else with di2 you can quickly plug your rd into their bike (unplug their rd) just to do a quick sanity check. will at least tell you if its the rd is working or not.
Thanks for all the tips! Looks like all 4 buttons work. I was able to get a battery reading. I'll check connectivity to the rd again.
I have seen one instance where the battery check worked, but the shifting did not because the plug at the shifter was not fully seated. These first generation Di2 systems have 4 wires to connect at the plug, so the plug could be partially in, but still not make all 4 connections. Make sure you use the connection tool and make sure the plug makes a solid click where it plugs into the shifter.