BMW Charger woes

[Gelandestrasse]

I've got the BMW version of the pictured charger, with a Hella plug on the end. Was working then stopped (plugged into a 2010 GSA). I've tried it on other bikes, too.

I get the error LED on constant (after the usual start-up 'all lights come on then go out apart from the green power light). The manual says it's because the battery is connected the wrong way or the leads are shorted together - but I have checked the plug and made sure I connect a battery the right way round.

Anyone had this before and knows how to fix?

Is there a better forum for this issue?

Many thanks in advance.

 

[Santa-2512]

New / old?

in warranty? out of warranty ?

They dont last forever... might be time to call it a day and procure another ??

 

[Gelandestrasse]

Thanks - I probably wouldn't have posted for help if the device was in warranty. And it is fairly clear I was after a fix rather than 'go buy another'. Ho hum.

Sorry if that sounded negative! I've an enquiring mind and it is rare anything goes wrong with these bikes/accessories without it happening to someone else before (who might have had a fix). So these 2 factors lead me to find a solution that doesn't involve landfill.

 

[Santa-2512]

No perfectly acceptable answer,

TBH if its potted inside, then its game over -if not you could have a fiddle , more than likely its a step down transformer or the step down is controlled via some circuitry

but the cost of parts may negate its fix value

 

[Neil W]

Probably throw away technology , I had two separate Battery Tender chargers (one a six bank professional unit ) that failed within weeks of each, brother in law is an electronics genius , he builds and designs computer components, vehicle tuning boxes , vehicle ecu's etc etc and he stripped them and said that basically it was not worth fixing them .

 

[botus]

No perfectly acceptable answer,

depends on if we want a society where we attempt to keep the planet alive

a "well made £150 charger with almost no use" totally dead
or a budget £11 quid one with three year warranty still working fine 7 years on

 

[landmarkjohn]

I have the grey BMW branded version of this charger. It only works in the sequence below (which I had a right trawl to find) when used on my 2008 GS. Other people and other bikes get different results and I see that yours was working. Still, no harm to try:


ATTENTION!!!! You must first turn the key on to the bike, then you plug the charger into the accessory socket, then you plug the charger into the wall for power, then you turn the key off.


Failure to do it this way will result in the charger not charging the battery and overheating.

 

[Gelandestrasse]

Did that, no joy.

I have the grey BMW branded version of this charger. It only works in the sequence below (which I had a right trawl to find) when used on my 2008 GS. Other people and other bikes get different results and I see that yours was working. Still, no harm to try:


ATTENTION!!!! You must first turn the key on to the bike, then you plug the charger into the accessory socket, then you plug the charger into the wall for power, then you turn the key off.


Failure to do it this way will result in the charger not charging the battery and overheating.

But then I don't have a can bus bike anymore. The instructions don't mention the bike needs a can bus, so it should work with my R100GSPD...?

 

[TLSgazza]

Did that, no joy.

But then I don't have a can bus bike anymore. The instructions don't mention the bike needs a can bus, so it should work with my R100GSPD...?

I Have the grey version too. As above when on the odd occasion I plug it into my GSA.
For my TL's I just plug it into the din socket I've fitted and turn it on and it works fine.

 

[dashfixer]

I've used a CTEK for about 15 years now. It's plugged into the bike all the time the bike is in the garage. Not cheap but very good as far as I'm concerned.

 

[SteveM]

It's the French plug you have on it. Probably started keenly but soon lost interest after a few hours and quickly surrendered completely.

 

[RadioFlyer]

How often have you seen or heard the term “CAN-bus” in the context of a compatible charger for the accessory socket? Way too often and almost always dead wrong.

“CAN-bus” is probably the most misused term in all of BMW-related forum electrical discussions. For an understanding of what the CAN-bus actually is and does I suggest reading the article on Wikipedia.

The ZFE (Zentrale Fahrzeugelektronik or Central Chassis Electrics) is one of several controllers on modern BMW motorcycles. Its job is to manage chassis electrics. It senses logical inputs from switches and responds by turning things (lights, horns, grip heaters…) on and off. It also monitors current draw. If the current draw exceeds a threshold then the circuit is shut down so the ZFE replaces fuses. If the current draw is below a threshold on a light circuit the ZFE assumes that there is a burned out bulb or a wiring fault and tells the Kombi (the instrument cluster) to display a warning. The ZFE manages the accessory port and shuts it down if too much current is drawn (> 5A). The ZFE also monitors the accessory port for the presence of a compatible charger and connects it to the battery for charging.

Compatible chargers are often referred to as “CAN-bus” chargers or some other term using “CAN-bus”. This is nonsense and has led to a great deal of confusion. This misuse of the term “CAN-bus” probably originates with charger vendors. Early on the vendors would characterize chargers as being suitable for “CAN-bus equipped” motorcycles as a way of saying that the motorcycle had a ZFE. Later the terminology morphed into terms like “CAN-bus compatible”, “CAN-bus charger” and “CAN-bus mode”.

The CAN-bus itself does not play a role in charging via the accessory port. That many say it does is part of the mythology.

The ZFE “listens” for a specific electrical handshake from a charger and if the handshake is present the ZFE connects the charger through to the battery. No CAN-bus messaging is required to accomplish this.

A ZFE compatible charger sends and repeats a pulse train to the accessory port. The pulse train starts with the charger presenting 12V to the port for 1 second. Then it waits for 150 milliseconds. Next it sends a series of ten 12V pulses each having a duration of 10 microseconds and spaced 100 milliseconds apart. It repeats this pulse train until it senses that the ZFE has connected it to the battery and then it starts its charging procedure.

Of course you can always attach a charger directly to the battery but BMW instructs you to not do so while the battery is installed in the bike. Why? The reason is that many modern chargers are “smart” and will try to recondition (desulphate) a battery if it decides that the battery needs reconditioning. The desulphation process involves the application of high voltage pulses to the battery and if the battery is connected in the bike then all the bike’s expensive electronics also get exposed to the high voltage pulses as well. So there is some risk of damage involved. BMW isn’t going to try to explain how to determine whether your particular charger has a desulphation capability or not so it just tells you not to charge the battery directly in the bike to mitigate the risk.

If you have a smart charger and intend to connect direct to the battery while the battery is in the bike you should read the charger’s manual to see if the desulphation mode can be disabled. I use the Optimate 4 charger in its “CAN-bus mode” (sic) direct to the battery because in that mode high voltage desulphation is deactivated. I can’t be bothered with charging via the accessory port.

 

[botus]

Early on the vendors would characterize chargers as being suitable for “CAN-bus equipped” motorcycles as a way of saying that the motorcycle had a ZFE. Later the terminology morphed into terms like “CAN-bus compatible”, “CAN-bus charger” and “CAN-bus mode”.

The CAN-bus itself does not play a role in charging via the accessory port. That many say it does is part of the mythology.

The ZFE “listens” for a specific electrical handshake from a charger and if the handshake is present the ZFE connects the charger through to the battery. No CAN-bus messaging is required to accomplish this.

A ZFE compatible charger sends and repeats a pulse train to the accessory port. The pulse train starts with the charger presenting 12V to the port for 1 second. Then it waits for 150 milliseconds. Next it sends a series of ten 12V pulses each having a duration of 10 microseconds and spaced 100 milliseconds apart. It repeats this pulse train until it senses that the ZFE has connected it to the battery and then it starts its charging procedure.

does your last paragraph in above excerpt not indicate that canbus compatible chargers are doing some messaging ?

the accessory socket in a conventional shutdown goes to sleep and disconnects - the comms coming from "compatible chargers" keeps the socket alive so it can reach the battery to charge it

an almost utterly pointless exercise i'll grant you - just fit a fly lead to the pos terminal and a chassis ground and fit any modern charger you fancy - and that way I don't stress the ZFE any more than a key on ride will

ah, I think I get it - via the accessory socket with the ZFE involved, keeps the charger aware of the drain modern vehicles have with alarm monitoring etc... but that's fixed with a fly lead by not going direct to the battery on BOTH terminals (and the ZFE can go to sleep fully) ?

 

[RadioFlyer]

No my paragraph says nothing of the sort.

Again, "CAN-bus compatible chargers" is a total nonsensical phrase. There is no CAN messaging. There is no CAN-bus involvement.

The pulses are merely an agreed upon electrical handshake between the ZFE and the charger.