BMW R1200RT/R1250RT Forum

Just to clarify, my BMW Canbus/Linbus compatible charger does the same .. ish as Firenailer observed when plugged into either of the accessory sockets i.e. gets to 100%, complete LED lit and 0.2A charging but never goes to the point where the display says batter charging complete and on to sleep mode as RT Man described it should ..... AND that's without the alarm on or the GPS plugged in. When I connect the same charger direct to the battery, the charger does the whole sequence nicely, just as it should. I just can't fathom what could be drawing the current (and I realise it could still logically be a faulty charger that doesn't handshake with the Linbus properly). Will get them to look at it when it goes in for its service but would really like to know if there is anyone out there who has had the same problem without the GPS connected.....? :wonder:

Looks like the BMW Charger has the SAE style connection lead.

Optimate do a lead which can be bolted directly to the Battery.



MotorWorks do a full range of leads etc., https://www.motorworks.co.uk/vlive/Shop ... A&spPage=1.

Thanks. Funnily enough, I've just ordered one of those but it doesn't fix the potential problem of why/whether there's always a 0.2A drain on the accessory socket... and a potential flat battery if I don't keep it on charge, if you see what I mean.

Steveeung wrote: Just to clarify, my BMW Canbus/Linbus compatible charger does the same .. ish as Firenailer observed when plugged into either of the accessory sockets i.e. gets to 100%, complete LED lit and 0.2A charging but never goes to the point where the display says batter charging complete and on to sleep mode as RT Man described it should ..... AND that's without the alarm on or the GPS plugged in. When I connect the same charger direct to the battery, the charger does the whole sequence nicely, just as it should. I just can't fathom what could be drawing the current (and I realise it could still logically be a faulty charger that doesn't handshake with the Linbus properly). Will get them to look at it when it goes in for its service but would really like to know if there is anyone out there who has had the same problem without the GPS connected.....? :wonder:

Your problem would seem to be a drain from the bike somewhere and not the charger which knows when the battery is fully charged and switches off. If you are not a huge distance from your dealer I would ask them to plug the bike in and see what's happening. And get them to plug your charger into another bike while there at it.

Yep that's the plan, thanks

RTman10 wrote: Firenailer.  You don't say what type of charger you plugged directly into the sockets.  Remember your bike had Canbus/Linbus wiring which requires a Canbus compatible charger to work properly.  The latest Optimate charger are OK as is if course BMWs own. Anything else can cause faults to the system.   

Hi RT,


Originally I was using the latest greatest BMW Charger shown in the pics Steve put up, this is the white square digital read out charger that replaced the older BMW charger that resembled a regular battery tender with the 3 lights. I have a nice collection of BMW chargers if anyone is looking for one : )


The problem is the shared ground wire that the power ports and GPS power plug share. Whatever slight draw the GPS is using causes the canbus to reactivate the power to that circuit and actually energize the GPS as if the switch was on. Bypassing it all and going straight to the battery via the SAE type cable I use for my electric vest, solves all of the linbus / canbus drama and keeps everything charged up just fine, keeps the GPS powered down, and has for months now.


Someone else asked about why leave the GPS on the bike, and I'd answer why not? It's in my garage. Why take it out of the cradle every time I come home. I do the same with my auto, it's mounted and stays there.

Firenailer this is really interesting. So... are you saying..

1. There IS actually a draw on the current from the battery all the time when the bike is switched off (that would logically flatten the battery if the bike wasn't kept on a trender / charger) or ....
2. There's NOT any actual draw of current from the battery i.e.  the wiring set-up only causes a draw from the new BMW charger when it is connected in the aux socket (and doesn't cause that same draw from either the battery itself OR a charger that is connected directly to the battery)?...

and are you saying it should only happen when the GPS is plugged in or whether or not its plugged in (which is true with mine i.e. there's a 0.2A draw on the charger when its plugged into the aux socket, whether or not the Nav IV GPS is fitted).

Everybody's different.  I leave my Nav V on the bike all summer in the garage. As you knew when you switch off the ignition the GPS invites you to shut it down or it will do it itself after 30 seconds. With the charger connected through an accessary socket it always shuts totally down when the battery is full.     

Thanks Firenailer for the answer on leaving the Nav V on the bike. As I pointed out all of this battery charger lark is all new to me, but I have gained a lot of intelligence from the thread. By the way my bike is kept in the hall of my house until I can get some other suitable accommodation. Luckily my wife whose last bike was an MVBrutale is understanding.

Steve,


Before I installed my GPS I used the same charger that you have. It would reach 100% and go into sleep or maintenance mode. Occasionally it would cycle through a charge cycle as the battery drew down from the clock, alarm and whatever other parasitic draws the RT might have.


If I removed my Garmin from the cradle it would perform the same way, only occasionally cycling. ( if I remember correctly). Since I've bypassed all of the powerlets and gone direct to battery I can leave my GPS in the cradle, unplug the charger, fire up the bike and roll out of the garage without wasting any time.


On a side note my original battery went totally dead in 2 years using that BMW charger. Since changing to a regular battery tender I'm getting much stronger starts and so far haven't  experienced any negative side effects to the electronics. I'm hoping for a much longer life as I've always gotten 6-7 years before changing batteries in the past.


Spencer - I'm jealous! I'd much rather park my bike in the living room than the garage. That's brilliant!

Right so I've now fitted the lead as in the photo David posted above and all works as it should ..... but the blinking service indicator is permanently on on the dashboard ...grrrr. Anyone had that one happen?  :grave:

The service light showing is probably because you have disconnected the battery and the date is wrong so it thinks it needs one.

Yep that sorted it thanks 

Top man RTman10 you're like a little genie in a bottle.

Well it turns out when aux lights are fitted to the LC they cause a fault on the aux sockets and have to be reset or the bike recoded. My dealer wasn't aware of this so there's a bulletin going out to all dealers. I wish it wasn't me who had to find these things out.  :beee: