Di2 anomaly (battery issue ?)

[Ridgeway]

Wondered if anyone can shed some light on a Di2 issue i've been experiencing.

Bike is approx 9 months old, around 4k km covered so in theory should have been possible with a single battery charge. 3 times now i've had what seems like a dead battery. The first time i just assumed the battery needed a charge so connected it up to a standard BCR2 and sure enough the orange light came on, but oddly it went out after 15mins and sure enough the system worked as normal. I decided to be sure i'd charge it over night, all OK work as usual and back to normal. About 4wks later (perhaps 700 km covered) it did the same again, totally dead (in both cases i found the battery to be dead only when i went to the bike after a couple of days ie it didn't die whilst out on a ride and during no ride did it display the "low power" feature of the front DR stopping to work). So recharged and all OK again...

This evening it did it for a 3rd time so it seems i need to sort this

In all cases the orange light on the charger went out after about 10-15mins which to me seems too short for it to be taking a full charge, maybe the battery isn't discharged at all ??? And yet in all 3 cases after this 10-15mins charge the system functioned fully normally when before it was totally dead

I would whip it back to the LBS but they are closed and no date when things like that will re-open here so thought it worth a quick check to see if i have missed anything obvious ???

I haven't yet connected it up to E-Tube as i don't have a PC (we're a Mac house) could borrow one if that seems worth trying.

 

[derrick]

Had a couple of problems with Di2 bikes belong to other people, First one the rear derailier was draining the battery over night, the battery was fine when i disconnected the derailier, when connected it worked fine on normal rides, Just fitted a new one, the second was to do with a bluetooth connector, Just took that of problem solved.

 

[Ridgeway]

Had a couple of problems with Di2 bikes belong to other people, First one the rear derailier was draining the battery over night, the battery was fine when i disconnected the derailier, when connected it worked fine on normal rides, Just fitted a new one, the second was to do with a bluetooth connector, Just took that of problem solved.

Cheers Derrick, I didn't install the bluetooth device so it shouldn't be that however i will investigate the first point

 

[Yellow Saddle]

Is the battery in the seat tube or is it an external one. First thing I'd do is use a multimeter to check the voltage when it is supposedly flat.

 

[Ridgeway]

seat tube, yes good idea. Need to figure out how to remove it first...

 

[Yellow Saddle]

seat tube, yes good idea. Need to figure out how to remove it first...

Just remove the seat tube with saddle and all. The cord should be long enough to get the tube out. Then you can just unplug it and measure. No need to remove the battery from the tube itself.

 

[Ridgeway]

ok great, thanks for the explanation. Will keep the multi meter handy for the next "power out"

 

[Yellow Saddle]

ok great, thanks for the explanation. Will keep the multi meter handy for the next "power out"

The voltage should be 7.4V or higher if the battery is good.

 

[Ridgeway]

you're a star, off to check it now even though it's just been charged it's worth a quick check to see if anything looks odd.

thanks again

 

[JhnBssll]

How is the bike stored? I left mine in the boot of the car for a day once with one of the shifter buttons accidentally depressed. The battery was dead when I got it out for the club ride that evening

I would also check all the connection - I've seen it before where one of the etube wires isn't fully clicked home allowing the system to seemingly work but with odd behaviour. Generally when I've seen this it won't charge, but if the bad connection wasn't between the junction box and the battery presumably it would. The connections around the bars are generally those most prone to being knocked, how far you go is up to you but I would start with just the easily accessible ones as any internal connections are unlikely to have been knocked...

Also I would contact the shop it came from, just in case there is a defective component. If it's only 9 months old it will still be under warranty so I'd be wanting to get it on record

 

[Ridgeway]

How is the bike stored? I left mine in the boot of the car for a day once with one of the shifter buttons accidentally depressed. The battery was dead when I got it out for the club ride that evening

I would also check all the connection - I've seen it before where one of the etube wires isn't fully clicked home allowing the system to seemingly work but with odd behaviour. Generally when I've seen this it won't charge, but if the bad connection wasn't between the junction box and the battery presumably it would. The connections around the bars are generally those most prone to being knocked, how far you go is up to you but I would start with just the easily accessible ones as any internal connections are unlikely to have been knocked...

Also I would contact the shop it came from, just in case there is a defective component. If it's only 9 months old it will still be under warranty so I'd be wanting to get it on record

Thanks, some more good points to explore. It's stored in a bike rack so no issue of any of the shifters being pressed (learnt that on my previous bike when it was in the bike trailer, protected it with some foam which in turn pushed the shifter in, all the way on a long drive = dead battery upon arrival). I'll take a look at the connections though and yes emailed the shop yesterday just in case, hopefully they can re-open next month

 

[C R]

The symptoms, battery supposedly dead, but reporting full charge after a short period of charging, suggest a fault in the sensing circuit or management system in the battery. Sounds like a warranty claim to me.

 

[Ridgeway]

The symptoms, battery supposedly dead, but reporting full charge after a short period of charging, suggest a fault in the sensing circuit or management system in the battery. Sounds like a warranty claim to me.

Thanks CR, the bike shops may be able to open next week, just waiting on a new government announcement but either way i will see what they have to say, hopefully they'll swap it out.