New battery

[Apex]

Varta £68 inc pnp; thats a lot easier to deal with......

[peterb]

Holy thread resurrection...

I coaxed another two years out of the original battery after buying a Ctek battery charger... But at ten years old I feel I'm on borrowed time, so I rang the Indy I spoke to last time, and the OEM battery is now just shy of £180, the same price as getting it from a BMW dealer, and they wanted to charge for registering a new battery with the car electronics.

So I ended up getting the Varta F21 from tayna batteries for £140 delivered.

My car is the E46 chassis, and doesn't have start/stop so I am still slightly confused why that battery is fitted. I checked again with a dealership about having the battery registered with the system electronics and was again told it wasn't needed. There is no evidence of a battery management system or Intelligent battery system connection on the ground/ chassis lead, but the positive terminal has several connections





The thin red wire is the charging connection for the CTek. The block with the bar code on it has two thin wires going to plug on the side, so that may be a sensor of some sort, although logic says that the only sensor it could be would be a current sensor.

So any BMW mechanics here, or anyone else, what's the score with battery registration? (Google search just throws up more confusion!)

[GoNz0]

Afraid the E46 has smart charging so it lowers the current on older batteries as they cannot take the full on amperage a new one can, You will find it undercharges the battery now so I would get it done. You can do it yourself if you have a decent interface module and the BMW INPA software, I think you need to tools32 program to register it.

That block with the barcodes got an explosive charge connected to the airbag system (hence the 2 small wires) to cut the battery at source, only about £500 to replace!

If you don't have the diagnostics you can always phone round and find somewhere who will do a quick hook up and register it for a backhander.

[listy]

sister company to eurocarparts sometime same parts are cheaper on here.... http://www.carparts4less.co.uk/ but im thinking you wont find what you need sorry its no help

[Zak33]

I think the BMW charging system is set for a particular battery style and capacity, per car model pete. I think that replacing it with an identical spec battery and you have to get it registered with the car because I think it determines the mileage when the battery came off the car, and a new one went back on. So BMW set the new battery mileage into the onboard system to monitor it being changed. Howver at 10 years old I don't know if that matters at all...

(Not sure if your car is new enough for that to occur meanifully.)

A newer BMW has an absorbed glass mat battery. They are totally sealed, very safe and charge very fast. Hence.. fitting a lead acid and it won't charge well enough with the default current from your alternator.

I did NOT know about the live terminal explosive charge though...

that is GENIUS.. and ultimately VERY BMW though long term I fear expensive one day.

[peterb]

The battery is an AGM, and they are usually fitted to cars with the start stop function, but mine doesn't have that. I have replaced it with the same type.

I did wonder if it was a safety measure as the battery is in the boot. It is also one of the last E46 models as a 55 plate, so they may have just upgraded the battery.

When I asked the dealership, they expected it to have a conventional lead acid battery and were surprised that it had an AGM when they looked up the car's specs.

The dealer reckons it doesn't need registering, the Indy did. Gonz0 thinks it does.

The E90s with battery monitoring have a sensor in the ground lead, which mine doesn't have.

I think I'll do a bit more ringing around tomorrow.

[GoNz0]

Odd, I understand you only need to register a like for like swap, changing types or CCA will require programming as well.
half of it is stats being the install date, mileage and possibly a serial number (dunno about the last bit)
and the other half is registering a reference point at 80% charge (just googled the 80% charge as I knew I had heard it before)

I doubt it will matter for a daily driver and probably cutting a fair chunk off it's expected life, maybe 4 years over 5 as it isn't a genuine that do seem to last 10 years, mine did fwiw and I got another 2 years out of it with my ctek as well as it turned into a weekend drive when I had the company van to nip out in. My e36 is a lot easier to work with, I started the engine at the motor factors, unhooked the battery and fitted the new one so I didn't have to reprogram the FM channels

That thing with the battery cable in the boot, maybe safety as the boot isn't firewalled as the 4 pots have the battery up front as it has room and that has no exploding cable, also not a feature in my e36!

Lets face it, if the airbags went off the last thing you would worry about is changing the battery cable as it is an instant write off at that age

[peterb]

Odd, I understand you only need to register a like for like swap, changing types or CCA will require programming as well.
half of it is stats being the install date, mileage and possibly a serial number (dunno about the last bit)
and the other half is registering a reference point at 80% charge (just googled the 80% charge as I knew I had heard it before)

I doubt it will matter for a daily driver and probably cutting a fair chunk off it's expected life, maybe 4 years over 5 as it isn't a genuine that do seem to last 10 years, mine did fwiw and I got another 2 years out of it with my ctek as well as it turned into a weekend drive when I had the company van to nip out in. My e36 is a lot easier to work with, I started the engine at the motor factors, unhooked the battery and fitted the new one so I didn't have to reprogram the FM channels

That thing with the battery cable in the boot, maybe safety as the boot isn't firewalled as the 4 pots have the battery up front as it has room and that has no exploding cable, also not a feature in my e36!

Lets face it, if the airbags went off the last thing you would worry about is changing the battery cable as it is an instant write off at that age

That reference refers to the E90 chassis, not the E46. However the replacement is an AGM, like the one fitted as OEM. Same capacity and same CCA rating.

I think Varta are one of the OEM for BMW, so I'd hope it lasts longer than 5 years! I'll ring another dealer and a couple of Indys tomorrow.

I did NOT know about the live terminal explosive charge though...

that is GENIUS.. and ultimately VERY BMW though long term I fear expensive one day.

Appears it isn't unique to BMWs, having done a bit of research...

Seems it disconnects circuits not protected by a fuse (basically the starter/charging ccts) in the event of an accident, while leaving secondary circuits intact.

Apparently the only repair option was to replace the cable , but BMW now do a repair kit.

[GoNz0]

yeah that repair kit seems to be the entire cable though?

That post seems to be an about a 2006 e46 even though it is in the e90 forum?


Have you asked any other dealers what the crack is with it?

[peterb]

Yes, went to local dealer who were still surprised that it had an AGM battery, but said that an AGM does, and quoted best part of £60 plus vat to do it - then added that they would only do it for a genuine BMW part.

Local Indy was again surprised it had an AGM, but confirmed that if it was, the battery did need registering, and quoted same price for recoding.

When I asked how long it took, he became a bit evasive, and when I said it was a battery with identical characteristics, he agreed to do it for £30 plus vat.

I did look at getting the software and connector, which costs slightly more than £30, but there seems to be a number of places where this could go wrong, so I'll grin and bear it.

I know the garage has to buy the kit, and has overheads etc, but £30 for a ten minute job...

As for the cable, it seems a new explosive connector can be crimped onto the existing cable, so a new cable doesn't need to be fitted along the length of the car. halving the cost from very expensive to just expensive!

[jimborae]

Lol I have had a brand new Bosch battery for an E46 sat in my garage for the last 2 years!!!! Bought just before I sold the car, you could have had it for a huge discount if I'd seen this thread. Having owned a late model E46 330ci I'm not convinced you need it coding either, certainly do on the E90, but people change batteries without doing it anyways to no ill effect.

[peterb]

Ah well, such is life! Is it the AGM battery? No matter, Ive fitted the replacement and booked it in to be registered, so job done. If the replacement lasts 10 years, I shall be happy!

But thanks anyway!

[jimborae]

No it wasn't an AGM, just sealed. Mine like yours could have either and it wasn't start stop so I just went for a normal one. My E91 is AGM but again is manual, no start stop but most 335 E91's are autos and have AGM batteries, so I guess they just stuck one in anyway for the manuals.

[peterb]

Apparently if you change types there is some coding to do. Mine was a 'pre-owned' car and had the AGM already installed. It's done well, it stated playing up in winter when I started this thread, at 7 years old. It survived the next two winters with the careful use of a battery charger, but probably time to retire it now, at ten years. It still started OK, but in cold weather it did need a boost from the battery charger before Inwent out, and with the new battery it starts instantly, rather than after a couple of turnovers.

So while this was a thread revival, I guess it has now run its course!

[peterb]

Well, I thought it was all clear...

So...

I took the car down to my local Indy, BMW trained mechanic.

Drove it into the workshop where he plugged in the diagnostics. Came back two minutes to say that it didn't need registering, and there wasn't any registering setting to be applied.

He also expressed surprise that it had an AGM battery.

So, end of story. It doesn't need registering with the ECU. However, I will investigate purchasing the diagnostic cable and software

Mnay thanks to all who contributed - I've learned a lot on the way!

[jimborae]

Well, I thought it was all clear...

So...

I took the car down to my local Indy, BMW trained mechanic.

Drove it into the workshop where he plugged in the diagnostics. Came back two minutes to say that it didn't need registering, and there wasn't any registering setting to be applied.

He also expressed surprise that it had an AGM battery.

So, end of story. It doesn't need registering with the ECU. However, I will investigate purchasing the diagnostic cable and software

Mnay thanks to all who contributed - I've learned a lot on the way!

Thought that might be the case, as far as I was aware the intelligent charging system was only introduced with the the E90 on the 3 series. As far as I know you can chop & change between AGM & normal batteries on the E46. Just make sure you keep the power specs about the same.

To be honest the diagnostic cable & software (coding kit) is also not as advanced as it is on the E90, i.e. there's not so much you can do and it's very easy to get things wrong with very expensive consequences. So unless you're dead set on doing a lot of research and faffing about with Win 7 32bit or even XP installs I wouldn't bother.

However if you are still interested then www.bmwcoding.com is a good place to start.