BMW Plus Charger "problem"

hawkeye

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Is there any way that anyone knows of to test a BMW Plus Charger (the black one)? Mine chgarges the battery ok, but won't go into float mode when plugged into the bike. I've also tried directly charging another perfectly good battery (off the bike using the crocodile clips instead) and again it charges ok - yet according to the manual its supposed to say "Charging Complete Battery Maint" when its fully charged and its not doing that.

In both cases I get fully charged 100% showing, with input of 0.2v and whatever the other display is of 14.4v when its fully charged (and the yellow and green lights on solid).

I appreciate that sometimes these can take some time to go into float mode, but in both cases I would have expected less than 24 hours to be sufficient (after that I just assumed that it wasn't going to do it) and it used to swap over to float mode after a couple of hours tops.

The charger was working perfectly well (as far as I was aware) until I changed my battery earlier this week (at least it was when plugged into the bike and happily went into sleep mode after charging the battery) for a new battery (same type as before Yuasa YTX14H-BS) as the previous one had started to show signs of a failing cell, so I decided to swap it out.

Given I've tested 2 separate batteries in different ways, I've a suspicion that as the charger doesn't now seem to interact with the CanBUS to go into float mode, nor does it do similar and display the "Charging Complete" message when charging the battery stand-alone, that the microprocessor inside it is stuffed and I need a new charger. But just thought I'd check with the wealth of knowledge on here before spending the best part of £90-odd quid on a replacement as to whether there are any checks I can do - or if there is a way to reset it perhaps.

Bike is a 2019 R1250GS. Thanks
 
I found that my Quad Lock wireless phone charger, plugged into the bike's USB socket, caused sufficient current drain to prevent the charger from going into 'power saving' (='float'?) mode, or possibly from concluding that charging of the bike's battery was complete.

The Quad Lock charger was on; its LED was on. So it seems the USB socket is 'live' when the BMW charger is plugged in to the DIN power socket on the side of the bike. When I unplugged the Quad Lock charger, the BMW charger then went into 'power saving' mode.
 
I found that my Quad Lock wireless phone charger, plugged into the bike's USB socket, caused sufficient current drain to prevent the charger from going into 'power saving' (='float'?) mode, or possibly from concluding that charging of the bike's battery was complete.

The Quad Lock charger was on; its LED was on. So it seems the USB socket is 'live' when the BMW charger is plugged in to the DIN power socket on the side of the bike. When I unplugged the Quad Lock charger, the BMW charger then went into 'power saving' mode.

Thanks - whilst I don't use that socket, I did wonder whether some of the additional items connected to the bike may have caused the issue so disconnected the lot - just leaving the battery connected - which made no difference. Found out that the battery is getting charged by the BMW Plus Charger as if I leave it on long enough, I do get the "Charging Complete" message that one normally gets when the battery is off the bike - its just not going into "float" mode. Bike is also charging the battery ok when I'm out and about. Whilst my old battery I removed has/had a cell possibly starting to fail, it would take a charge standalone (and indeed I got the "charging complete" message), so temporarily put that back on and tried it again through the socket - which made no difference. Tried it again with the original OEM battery - same result. So potentially seems that the battery is not the issue.

So where I'm at at the moment is:
- the bike itself is charging just fine (14.3/14.4 at tickover and when out and about)
- bike itself runs no problem when in use, everything works just as it should when out and about
- its none of the accessories I may have fitted causing a draw (as get the same "issue" with everything disconnected)
- batteries when connected stand-alone will complete their charge (tried it on 2 separate batteries) and the charger gives the correct "Charging Complete" message.
- its only when the battery is being charged through the socket that it won't go into float mode at the end of charging - instead giving a "Charging Complete" message (as though its connected off the bike, rather than being charged through the socket) - so is not "communicating" with the CanBUS/ECU when connected to enable "float" mode

My gut feel still is that the charger is at fault, Having now researched and read up on how the BMW Plus charger works, also on how the Optimate4 Dual Charger works, it would appear that the Optimate is possibly a better bet than the OEM BMW Plus, so I've purchased an Optimate 4 Dual Charger which works across the battery and/or with the CanBUS/ECU (depending on the mode chosen) which should arrive tomorrow, so will try that, both through a pigtail and also through the socket and see where that gets me. If that makes no difference, then it will get charged through the pigtail for the time being and having chatted to my dealer today, next time its in for a service (in about 1k miles), I'll get the workshop to test the BMW Plus charger with the bike during the service (they have to have the bike overnight for its 12k service).

Overall its not causing me any issue with riding the bike, but knowing it doesn't work is just bugging me now, and I want to know definitively if its the bike or the charger. Hopefully not the bike!
 
Overall its not causing me any issue with riding the bike, but knowing it doesn't work is just bugging me now, and I want to know definitively if its the bike or the charger. Hopefully not the bike!

Yes, I'd be the same. I like things to work, and do what they're supposed to do.

BTW, I've assumed that 'float' mode *does* correspond to the yellow 'power saving' LED on the BMW charger flashing; is this correct? The characters on my charger's LCD also go faint / no backlight.
 
Yes, I'd be the same. I like things to work, and do what they're supposed to do.

BTW, I've assumed that 'float' mode *does* correspond to the yellow 'power saving' LED on the BMW charger flashing; is this correct? The characters on my charger's LCD also go faint / no backlight.

Absolutely correct @FurryFox, the power saving LED flashing is when it is in "float" mode.

Anyway - the good news is that I've found the problem!!! After getting my new Optimate charger delivered today, only to find it was the wrong one (grrr!), I decided it was time to get back to basics, so took off all the additional gadgetry I've added through Hex-Ezcan and also which take power from a switched source using leads direct to the battery - in my case my INNOVV K3 camera. Started by charging the bike using the BMW charger with just the battery connected, nothing else, and it charged just fine and went into float mode. Added the Hex-Ezcan and it charged just fine and again went into float mode. Added my INNOVV K3 camera and.....nope. Took everything else off and just had the INNOVV on there. Nope. Whilst the camera seems to be working perfectly ok, for some reason its confusing the ECU/CanBUS charging when both it and the ignition are off. I only found this late this afternoon, so have yet to finish stripping down the bike to get the DC Converter unit off and test/inspect it properly, But certainly with that disconnected, the charging circuit works as it should and the charger goes into 'float' mode as it should. Which puts my mind at rest as at least I know what the issue is, and if the DC Converter is the issue, then its under £30 from INNOVV if I do need a new unit and all will be well again (i'm wondering whether I've somehow pinched a wire somewhere between the converter and the battery when changing the battery, in which case its fixable.

Thanks for your input @FurryFox, what you posted made me think a little further outside the box. Also to @knutk as in searching for articles on this forum, I came across a post he made some time back which helped my understanding of how the bike and the items connected to the socket interact, al so others who have posted up about other charging issues. A whole wealth of knowledge on here.

But the good news is I know what the problem is now! Hated not knowing that!!!
 
...if the DC Converter is the issue, then its under £30 from INNOVV if I do need a new unit and all will be well again (i'm wondering whether I've somehow pinched a wire somewhere between the converter and the battery when changing the battery, in which case its fixable.

I suspect that the DC convertor may not be faulty; it may have a residual current drain via its direct connection to the battery even if its ACC wire isn't live. Maybe ask INNOVV what the convertor's current drain is, in 'off' mode? INNOVV may say that there will always be a slight drain, even when 'off', that may be enough to cause the issue with the BMW charger.

A pinched wire causing current drain to occur would imply a short from a +ve wire to ground (frame); that would probably be much more serious than a few mA drain on your battery, and would either blow an inline fuse or shut down the DC convertor (depending which side of the DC convertor the pinched wire was).

Perhaps also consider powering the the INNOVV DC converter via your ezCAN, instead of directly from the battery?

I should say, though, that I have neither an ezCAN nor an INNOVV camera system myself, however I may fit both in the future.
 
Well, having taken out the DC Converter and inspected it, it all worked ok, and no issues with the wires. Put everything back together carefully (re-routing a few wires in the process) and now everything works ok and the charger is working as the charger should, going into float mode once fully charged. Guess I may never know exactly what caused the issue, but hopefully it will never return! Either way, all is good - at long last!
 
Well, having taken out the DC Converter and inspected it, it all worked ok, and no issues with the wires. Put everything back together carefully (re-routing a few wires in the process) and now everything works ok and the charger is working as the charger should, going into float mode once fully charged. Guess I may never know exactly what caused the issue, but hopefully it will never return! Either way, all is good - at long last!

Good. Odd that it should've 'fixed' itself like that. I did notice that mine does take quite a long time before deciding its job is done for now, and that it can go into power saving / float mode.
 


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