Dead battery

[moonstone]

Got a call from the detailer this morning to say that the battery on my key must be flat as he can’t open the M5. Headed round and the car is a totally dead.

He’s had it since last Thursday. Last report from the car on the app is two days ago when he last worked on it. Says he had the boot lid open but that was it.

Put it on charge using my NOCO genius charger. Tried it on supply mode first but still not enough juice for the starter button to even acknowledge the key is in the car or for any electrical systems at all.

So it’s now sitting charging at the moment. The only accessory that’s connected is my dashcam but it is powered by a separate battery that charges from an ignition live, so it’s not draining anything when the car isn’t on.

Also the car normally announces that it’s shutting systems down if the battery gets too low.

Going to leave it sitting on charge at the detailers and collect it in a day or so, but as is the norm I’m worried I might have a bigger problem.

Anyone have any experience or words of reassurance!?

 

[boba fett]

I would imagine he has had more than just the boot open, in and out, moving it around, even so the boot open for some time would do it. These cars are so reliant on a well charged battery. You have had it for a while now and not had this issue, so its not a coincident! At this point I put it down to detailer failure as some put the car on trickle charge to prevent such things!

 

[moonstone]

That’s the thing, never had any issues so far so hopefully a charge will do it. Was slightly worrisome that even connecting the charger in supply mode didn’t make any difference. Still couldn’t even wake the car up.

Here’s hoping all ok.

 

[Grunty-Motor]

my experiebce is also that they shut down, rather than go flat. very strange.

is this one of these £800 lithium batteries?

 

[EvilDrPorkChop]

How old is the battery?

 

[moonstone]

my experiebce is also that they shut down, rather than go flat. very strange.

is this one of these £800 lithium batteries?

BMW charge £1900 apparently.

 

[moonstone]

How old is the battery?

No idea. Assume 4 years as old as the car.

 

[boba fett]

BMW charge £1900 apparently.

WTF!

 

[EvilDrPorkChop]

No idea. Assume 4 years as old as the car.

Probably need a new battery then.

Ours in our vans are now only lasting 3 years. I’m on my second battery in 7 years, our mechanic says it’s a common occurrence in all cars and vans now.

Some people on Bimmerpost have needed new ones after 3 years too.

 

[moonstone]

Probably need a new battery then.

Ours in our vans are now only lasting 3 years. I’m on my second battery in 7 years, our mechanic says it’s a common occurrence in all cars and vans now.

Some people on Bimmerpost have needed new ones after 3 years too.

I always thought that Lithium Ion batteries were supposed to last much longer.

 

[JMS]

My last L200 truck was on its original battery and sold that as it clicked over 10 years old. Only thing that needed was an alternator which I picked up for 30quid used and was fine fir another 40k miles before I moved it on.

Im sure things are manufactured to have a limited shelf life these days. Or thats how it seems.

 

[moonstone]

Sorted and shared more in-depth details here to help anyone else ever in the same boat: https://www.deutschespeed.com/threa...lies-to-all-bmw-m-cars-with-li-batteries.713/

 

[moonstone]

So… not quite sorted after all.

After charging the battery up I was getting a “faulty battery message” on the dash and I discovered that the windscreen wipers weren’t working. Also various fault codes when connected to the BMW workshop software.

Car went into a BMW indy today. New wiper mechanism required. The motor is burnt out and it all comes as one unit (£408 for the part). New BDC module required (£600) and coded. Total cost is £1700 on top of the £629 that I spent on the new battery that I fitted on Saturday.

I am not a very happy bunny.

 

[boba fett]

So… not quite sorted after all.

After charging the battery up I was getting a “faulty battery message” on the dash and I discovered that the windscreen wipers weren’t working. Also various fault codes when connected to the BMW workshop software.

Car went into a BMW indy today. New wiper mechanism required. The motor is burnt out and it all comes as one unit (£408 for the part). New BDC module required (£600) and coded. Total cost is £1700 on top of the £629 that I spent on the new battery that I fitted on Saturday.

I am not a very bunny.

Sorry to hear that, remember the problem I had, when it blew the FDM module, and disabled all the lights, indicators and wipers, sucks!

Mine was a known problem, no doubt this looks like another, not great at all?

 

[EvilDrPorkChop]

Guess that's where having the approved warranty would help. Although isn't there an excess on the BMW one?

 

[moonstone]

Guess that's where having the approved warranty would help. Although isn't there an excess on the BMW one?

I had the option to renew the warranty as the approved used warranty just expired in January. However there's a new warranty provider behind the insured BMW warranty now and they will not cover modified cars at all. The level of warranty that would have covered this would have been a grand and that would exclude the battery and come with a £200 excess. Also the fact my car is modified is a get out of jail free card for any potential claim. So given what I'd read on how strict they were now being, I didn't bother.

 

[moonstone]

Sorry to hear that, remember the problem I had, when it blew the FDM module, and disabled all the lights, indicators and wipers, sucks!

Mine was a known problem, no doubt this looks like another, not great at all?

The frustrating thing is we've no way of knowing what's caused that. It could be that our first attempts to jump start the car or the battery have fried it. Apparently one of the relays is knackered but BMW in their wisdom have made these relays part of the module itself rather than plug-in units.

It may have been me that knocked the wipers on and with the car then charging for two days the wipers have come back to life and been sitting on constantly for two days.

It's just one of those situations where any number of things could have gone wrong with no idea of really knowing what's been the precursor to a series of problems.

I'll just need to put it down to experience.