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Di2 Battery Mount

shooter999shooter999 Posts: 143
edited April 2017 in Workshop
Hi Everyone,

I've got one of the older 10 speed Ultegra Di2 systems with the external mount.

Over the last week or so if I leave the battery on the bike (as I've always done) the battery would be flat in a couple of days. I've also got the di2 wireless unit which communicates with my Garmin to tell me how much life is left in the battery.

This is the process I've followed to try and diagnose the problem:

1. To eliminate it being the battery, I fully charged the battery, and every night I connected the battery to the bike and it was still at 100%.

2. I then fully charged the battery and left it connected it to the bike, and within a couple of days the battery was flat, which suggests the one of the Di2 components was draining the battery.

3. I then fully charged the battery and connected it to the bike, but removed the cable attached to the battery mount and after a couple of days the battery was flat.

This suggested to that it was the battery mount that was faulty (apparently the most likely culprit).

I purchased a replacement battery mount

I've connected the battery to the new battery mount and that to the Di2 cable, however nothing happens. Does the new battery mount have to be "installed" to work with my system?

Apologies for the long post!


  • meanredspidermeanredspider Posts: 12,337
    I think your logic might be flawed. It's more likely to be the battery than the mount if it's going flat.

    Anyhow, your new mount probably has different firmware than the rest of your system - which probably means updating your system. But my money is still on the battery.
    ROAD < Scott Foil HMX Di2, Volagi Liscio Di2, Jamis Renegade Elite Di2, Cube Reaction Race > ROUGH
  • shooter999shooter999 Posts: 143
    A quick update on this.

    Fitted the battery mount and applied the latest firmware to all components, which seems to have fixed the problem.

    Went out for a 90 mile ride yesterday, and left the battery on the bike overnight and today. Just checked, and the battery is still at 100%.
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