Is my AGM battery knackered?

Nobbie1967

2012 BMW 116D on original battery. I've just noticed that the Start/Stop has stopped working even when it's all warmed up and aircon off. Checked battery voltage this morning and it was 12.33V despite a decent run out on Sunday. Does this sound like time for a new battery? No indication on dash that there is a problem with stop/start.

If it does require a new battery, apart from buying an AGM one of the right capacity and CCA, are there any special things I need to do when changing it? Do I need to keep power applied? Do I need to tell it about the new battery?

Modern cars, what a palarver!!!128512;

TadleyBaggie

My car (not BMW) needed a new battery last year. In the weeks leading up to the failure (total loss of charge after being parked up for a few days) the only thing I noticed was that the Start/Stop was never kicking in.

I had the battery changed by the RAC under warranty, after changing the battery he had to reprogram the car to accept the new battery.

GunJack

Nobbie1967 wrote: »

Modern cars, what a palarver!!!

Quite, another reason for buying older cars

Gloomendoom

Unfortunately, BMWs need new batteries "registering".

Nobbie1967

Gloomendoom wrote: »

Unfortunately, BMWs need new batteries "registering".

Yes, I'm just finding this out, may just drop in at my local garage and see if they can do this rather than start buying a bit of kit I'll use once. From what I've read it seems you need an OBD battery gadget for about £80.

neilmcl

Nobbie1967 wrote: »

Yes, I'm just finding this out, may just drop in at my local garage and see if they can do this rather than start buying a bit of kit I'll use once. From what I've read it seems you need an OBD battery gadget for about £80.

That'll cost you. The last time I had a new AGM battery for a 1 series installed by the dealer I think it was nearly £300 all in.

Nobbie1967

neilmcl wrote: »

That'll cost you. The last time I had a new AGM battery for a 1 series installed by the dealer I think it was nearly £300 all in.

I'll do the mechanical install myself, and just get the garage to do the registration thing with the OBD. It's not a BMW dealer, but assume they'd have this sort of kit.

TBH, £300 isn't too bad considering the batteries I've looked at on Tanya are £185 delivered for a Bosche S5, around £150 for Varta etc.

markudman

OK with a BMW you have to follow a procedure, if not you can put the car into Transport mode with will stop certain things working like central locking, electric windows etc, and once the battery has been replaced, you need to tell the car its had a new battery.
This may help.
https://ilikekillnerds.com/2015/10/replacing-a-bmw-battery/

Nobbie1967

markudman wrote: »

OK with a BMW you have to follow a procedure, if not you can put the car into Transport mode with will stop certain things working like central locking, electric windows etc, and once the battery has been replaced, you need to tell the car its had a new battery.
This may help.
https://ilikekillnerds.com/2015/10/replacing-a-bmw-battery/

Perfect, thanks!!!128578;

reddwarf2002

Unfortuntaely BMW batteries do need coding otherwise they don't last as long or might not function correctly. If you are very lucky you might be able to get away without coding it. But since AGM batteries aren't exactly cheap I would advise against it for the little extra that you need to fork out for registering.

Where abouts are you? Someone close to you that has the tools might be able to do it for a lot cheaper than the dealer/garage. If you were close to me I would've been able to code it for you.

Nobbie1967

reddwarf2002 wrote: »

Unfortuntaely BMW batteries do need coding otherwise they don't last as long or might not function correctly. If you are very lucky you might be able to get away without coding it. But since AGM batteries aren't exactly cheap I would advise against it for the little extra that you need to fork out for registering.

Where abouts are you? Someone close to you that has the tools might be able to do it for a lot cheaper than the dealer/garage. If you were close to me I would've been able to code it for you.

I'm in Wilmslow, just south of Manchester.