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DI2 7970 DA - won't go into adjust mode

DaviddkDaviddk Posts: 8
edited July 2015 in Workshop
Hi Guys first post here, hope anyone here can shed some light on the issue i'm having.

I bought a used DA 7970 DI2 groupset, before installing I plugged in everything and couldn't get any movement in the rear derailleur. Quickly noticed that there was a cut in the cable between Junction box A (control unit) and the right shifter. The green wire was cut right through, so some very fine soldering was done. The other 3 wires were intact.

Connected all plugs again and now the derrie was working just fine!

Installed everything on the bike, put a 10 speed wheel in and started setting everything up. I noticed the rear derrie didn't go onto the smallest cog, and overshoots the biggest cog thinking there was another cog. So when on speed 6, the derrie was on speed 7.

But otherwise everything works fine. Front shifter works good and trims along with the rear speeds.

I hope this is just a simple matter of adjusting, but I can't seem to get the unit in "adjustment" mode. Pressing the button on Junction box A short or long or whatever only quickly flashes the red light.

Also read that when you push a shifting lever and keep pushing, the green battery light should light up, but this doesn't work either.

Anyone experienced this before?

Posts

  • rafletcherrafletcher Posts: 1,235
    The "missing the cogs" is nothing to do with the adjustment mode. You need to set the upper and lower limit screws to set the travel correctly. I assume you've done that? Adjustment is just to trim the indexing between gears - you have I assume downloaded and read the dealer manual?

    Why solder a cable you can buy for £20? False economy IMO.

    Assume you've fully charged the battery before trying all this?
  • DaviddkDaviddk Posts: 8
    The "missing the cogs" is nothing to do with the adjustment mode. You need to set the upper and lower limit screws to set the travel correctly. I assume you've done that? Adjustment is just to trim the indexing between gears - you have I assume downloaded and read the dealer manual?

    Why solder a cable you can buy for £20? False economy IMO.

    Assume you've fully charged the battery before trying all this?

    If you can link me the cable I need for that price, I'll buy it. But still, a 10 min solder job so I can save £20, why the hell not.

    But I'm afraid you're referring to the second gen cables... For the first gen, all cables are fixed to the junction box and the whole loom costs £100 and isn't available anywhere.

    Anyway, when my right shifter is shifted to the lowest gear (won't switch any further and motor won't budge).. the chain is on the 2nd smallest cog, and still far off the limit screw but it won't go to the smaller cog. So I assume it's always one speed off and needs adjusting. I've set the outer limit screw so it won't overshoot the sprockets anymore. But this doesn't stop the motor from trying though.
  • trailflowtrailflow Posts: 1,311
    the derrie

    The What ? :x :)

    Try resetting the system (if you can). It may have gone into protection mode.
  • DaviddkDaviddk Posts: 8
    the derrie

    The What ? :x :)

    Try resetting the system (if you can). It may have gone into protection mode.

    Sorry, Belgian guy here, that's our short word for derailleur. :D
    Well, that's the whole issue actually...

    To reset you need to press the junction box for a longer period.. but nothing happens. Besides the red light blinking once after a second.

    Held it for 5 - 10 even 20 or 30 seconds, does nothing more than blink at me after a second. A very short press does nothing. And holding it down for a second just blinks the light once.

    Oh and battery is/should be fully charged, front shifts like a dream and his motor asks the most voltage.
  • trailflowtrailflow Posts: 1,311
    I think the red light is telling you there is a fault.

    I dont think you have many other options other than to try/buy a new junction box wire loom.

    Who did you buy it off ? Perhaps they knew about the fault and the cut in the wire but didn't tell you. Maybe think about getting a refund ?
  • DaviddkDaviddk Posts: 8
    I think the red light is telling you there is a fault.

    I dont think you have many other options other than to try/buy a new junction box wire loom.

    Who did you buy it off ? Perhaps they knew about the fault and the cut in the wire but didn't tell you. Maybe think about getting a refund ?

    Probably, but weird that I can't find anything about it or no one that knows more about it either..

    He did give me a small partial refund because of the cut wire, said he didn't know about it and that it might have happend during disassembly.

    Too bad the loom is so hard to find, and that there aren't many people/shops having it laying around to test with. LBS said he might still have the old diagnostic tool, but didn't have any time this week. :evil:
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