I purchased a new Cervelo P3 (2014) Ultegra Di2 in April. No problems with Di2 until a few weeks ago. I could easily go 500-700 miles between charges. A few weeks ago the battery went completely dead 3 or 4 days after charging with hardly any riding. The first time i didn't think much of it and just recharged the battery for my ride the next morning. This happened again a few days later and I took it to my LBS where i purchased the bike. They ran a diagnostic test on the Di2 system and other than a few firmware upgrades everything checked out fine. So, I got the bike back 4 days ago with a fully charged battery, road it about 30 miles 3 days ago and this morning battery is completely dead again.
I bought this bike for IM Louisville (Aug. 24) and I have to ship it on (Aug 15), 6 days from now. My LBS techs have been helpful but i am nervous that they really don't know what the problem is. I've reached out to them again this morning and they got back to me. He seems to think its a problem with the system not going to "sleep" like it should when not in use. He's going to contact Shimano.
The bike was brand new, no accidents, its been stored inside, etc. there is no clear reason that I can think of as to why something would have gone wrong. At this point, given that I am running out of time I think my LBS just needs to replace any and all of the Di2 components that could be the problem. I think Shimano has a 2 year warranty on their components to hopefully this won't be big deal.
Has anyone experienced this problem? I will be calling Shimano obviously but any other advice is greatly appreciated.
I have the same problem. Using Ultegra Di2 for more than 2 years now. Used to charge every 1500 km's or so, or sooner when going for a bigger event. Since this week my battery discharges within 6-12 hours. Started after a very wet ride, but my dealer says that cannot be the reason. Dried all connections, but problem persists. Maybe the battery has run out of life, which would be a disappointment after just 2 years. Ordered a new battery (want to have a spare anyway !!) and will see if that fixes the issue. Will let you know in a few days.
I had this problem, too, with my internal Dura Ace battery . It started with just missing a shift every now and then. Took it to the shop to check out and they checked all the connections, battery charge and ran diagnostics, etc. They didn't find anything wrong and it worked fine for a few days then DIED completely on me during a race (when I was in a 2-man break with a 2 minute gap on the field and just 10 miles to go. I was in the 34-19 after a hill and no way to finish the flat course in that gear!!!). Tried recharging battery and running diagnostics again. Diagnostics said no problems, but the missed shifts persisted. Finally got Shimano to warranty the battery and replaced it. No problems since replacing the battery.
Interstingly, I was watching the Tour of Utah on Saturday (8/9). Tom Danielson had to get a bike change during the stage and in his interview after the race he said something to the effect of "I don't know what happened. It stopped shifting. Maybe the battery became disconnected in the seatpost." I'm starting think that Shimano has a battery issue.
I promised to get back once I purchased a new Di2 battery. Installed the new battery, but the problem persisted. So it was not the battery. I then started to isolate every part of the Di2 system (rear derailleur, front derailleur, left shifter, right shifter, etc) by de-connecting the cable and then monitoring whether the battery was still draining within 24 hours. The method succeeded, and I found that the batteryholder was defect. Replaced the batteryholder, and the problem was solved. Shimano kindly offered to pay for the replacement battery holder.