Battery discharging while parked

[wattster1]

I have a similar problem to yours with my 2016 R1200RS, but it only happens occasionally. I noticed that once in a while when I went to start the bike, it would either struggle, or would not start due to low battery voltage. I checked the battery drain and found that it had a constant 50-80mA drain when that happened. Because of this I now check the battery voltage a few hours or the day after I use the bike. If the voltage is low, I can usually fix the issue by starting the engine and running it for a few minutes then shutting if off. I have done some testing, but have not been able to come up with any reason for the problem or a solution.

Since your problem is constant and seems to go away when you pull the 10A fuse I would suspect the rectifier/regulator might be the problem. Rectifiers have diodes, and when they fail they can cause a short to ground, which will end up discharging the battery after a few hours. Pulling the 10A fuse would isolate the rect/reg from the battery and prevent that problem. You can check this by unplugging the rect/reg and replacing the fuse, then checking the battery current drain.

It was disappointing to hear that the dealer told you that 0.25A discharge current was normal with the engine off. They either don't know what they're talking about or were intentionally lying to you as that is not even close to being normal as my bike has less than 1mA drain when off (measured with a Fluke multimeter). I hope they didn't charge you for that diagnosis. If they did I would report them to the BMW USA Customer Service about the lousy service: CustomerService@bmwmotorcycles.com

 

[Moretti]

Found this video about diagnosing a parasitic draw on an RT as I was preparing for a long ride this month and was having similar frustrating battery issues. Never ended up trying it out as I just replaced my battery with a lithium and have had zero draining problems since.

https://youtu.be/AhqZwLnD9Jk

 

[kbowman]

was disappointing to hear that the dealer told you that 0.25A discharge current was normal with the engine off. They either don't know what they're talking about or were intentionally lying to you as that is not even close to being normal as my bike has less than 1mA drain when off (measured with a Fluke multimeter). I hope they didn't charge you for that diagnosis. If they did I would report them to the BMW USA Customer Service about the lousy service: CustomerService@bmwmotorcycles.com

I'm going to Kansas next week for a project, and I'm planning to drop the bike at Engle Motors in KC the next weekend. (I'm trailering the bike.) I spoke with Ed in the service department earlier this week, and he said they'd look for a current drain.

I'm going to call the other dealer tomorrow just to let them know that their suggestion (a new battery) didn't work. I was surprised, but appreciated that they didn't charge me for the diagnosis since they couldn't find anything wrong.

Ken

 

[kbowman]

Battery discharge finally solved

I thought it might be helpful to others to provide the final outcome to this thread.

As I said in my previous message, I had an extended work period in Kansas last summer (I live in Texas), so I took the bike with me on my trailer and dropped it off at the dealer in Kansas City. They had the bike for 5 weeks and eventually diagnosed a bad relay for the aux lights. They replaced the relay, but when I went to collect the bike the battery was dead, so the relay was not the source of the problem. Because they had not been able to fix it, they refunded the labor they charged me. I only paid for the relay ($50), but left with the problem unresolved.

When I got back to Texas I did some carefuly battery monitoring under different conditions (e.g., aux lights connected vs. not connected) so that I could convince the dealer it was a real problem. I was finally able to get a service appointment at the dealer in Austin. They had it for over two months, and eventually decided/agreed to replace the ground module, which I had pointed out to them as a possible problem when I dropped the bike off. (Thanks to eplerd for finding that thread in the ADVrider forum!) The total cost was $960, $501 for the part.

I have had the bike since early December with no problems, so last week I reconnected the lights and went for a ride. I am able to report that the battery is holding a charge, and everything seems to be working again!

This is the first major problem I have had with the bike since I bought it new (2015 model, 44k miles), and this is not a complaint about BMW reliability, but man it took a long time to fix.

Here is a photo of the part, in case anyone is interested or needs the part number. Out of curiosity I opened the case (with a hacksaw). Inside is a printed circuit board that fills the case; it has many chips on it. Beyond that I did not learn anything of use.

Cheers, Ken

 

[mikegalbicka]

Thanks for reporting back on the solution.

 

[cap]

What is the function of the “ground module?”

 

[ramble]

Can you post a pic of the modules location on the bike, and describe it? Thanks for the update to the forum.

 

[kbowman]

Can you post a pic of the modules location on the bike, and describe it? Thanks for the update to the forum.

Sorry, I have no idea since I didn't do the repair myself. Buried somewhere inside the frame is my guess.

Cheers, Ken

 

[pauls1150]

I found a few "modules" in the parts fiche, starting with 61358, but nothing called a "ground" module...

EDIT: I tried correlating the RealOEM info against the MAX fiche, and nada... grrr...

 

[easy]

I thought it might be helpful to others to provide the final outcome to this thread.

As I said in my previous message, I had an extended work period in Kansas last summer (I live in Texas), so I took the bike with me on my trailer and dropped it off at the dealer in Kansas City. They had the bike for 5 weeks and eventually diagnosed a bad relay for the aux lights. They replaced the relay, but when I went to collect the bike the battery was dead, so the relay was not the source of the problem. Because they had not been able to fix it, they refunded the labor they charged me. I only paid for the relay ($50), but left with the problem unresolved.

When I got back to Texas I did some carefuly battery monitoring under different conditions (e.g., aux lights connected vs. not connected) so that I could convince the dealer it was a real problem. I was finally able to get a service appointment at the dealer in Austin. They had it for over two months, and eventually decided/agreed to replace the ground module, which I had pointed out to them as a possible problem when I dropped the bike off. (Thanks to eplerd for finding that thread in the ADVrider forum!) The total cost was $960, $501 for the part.

I have had the bike since early December with no problems, so last week I reconnected the lights and went for a ride. I am able to report that the battery is holding a charge, and everything seems to be working again!

This is the first major problem I have had with the bike since I bought it new (2015 model, 44k miles), and this is not a complaint about BMW reliability, but man it took a long time to fix.

Here is a photo of the part, in case anyone is interested or needs the part number. Out of curiosity I opened the case (with a hacksaw). Inside is a printed circuit board that fills the case; it has many chips on it. Beyond that I did not learn anything of use.

Cheers, Ken

Don't be surprised at the wait for service at the dealerships. We are not even close to being over the pandemic. The week ending 1/22/2022 had 5,883 Covid-19 involved deaths. That's almost two 9/11s. https://www.cdc.gov/nchs/nvss/vsrr/covid19/index.htm

E.

 

[mikegalbicka]

There is a little info on the thread previously linked

https://www.advrider.com/f/threads/...y-drain-resolved.1173435/page-9#post-30671194

 

[ff73148]

I had a Moto Guzzi Bobber that had the same problem. I narrowed it down to the alarm immobilizer. The immobilizer stayed active for five days thus draining the battery. Do you have an alarm system on this bike? If so you might have activated it when you initially changed the battery.

 

[cap]

What is the function of the “ground module?”

Searching with google for the part number… it comes up as a “basic module”. And it seems to be related to the ECU or ECM.

And that adds exactly nothing to our understanding of the function of this device.

 

[Omega Man]

Seems I remember something about these new systems are switching a device to “on” by completing the circuit to ground. This is different than “sending” power to the device.
OM

 

[pglaves]

Seems I remember something about these new systems are switching a device to “on” by completing the circuit to ground. This is different than “sending” power to the device.
OM

Exactly like the R60/5 horn button.

 

[Omega Man]

Exactly like the R60/5 horn button.

Or….my old Dodge horn button.
OM