[Dan-]

Sure this has been aposed a few times before but I'm just looking for some advice, looking to change my battery in my e92 335d but my original has already been changed with a bosch S3 95AH, me not being able to tell what should be in the car from factory I rang BMW to see if they could tell me what spec battery I had when new, and they're telling me that on there system it is a AGM 90AH strange as I don't have Start/Stop function, if I was to take it there that what I would have fitted. Been told this by seperate dealers now.

What should I do, I've got a Bosch S5 100AH/830cca at home I've bought, should I return this I buy an AGM bosch S6 95AH

Thanks in advance!

Dan

[Hulla the Hulla]

You don't have to have start / stop to have an AGM. I think the question to ask yourself is what is the standard / correct spec of battery for your car ?

[Dan-]

Originally Posted by Hulla the Hulla

You don't have to have start / stop to have an AGM. I think the question to ask yourself is what is the standard / correct spec of battery for your car ?

Yeah the issue I'm having, bmw are adamant it's 90ah AGM but how do I know there not just trying to get money out of me, £200 for the battery and £90 registering, won't register a battery I supply

Dan

[old grey steve]

Originally Posted by Dan-

Yeah the issue I'm having, bmw are adamant it's 90ah AGM but how do I know there not just trying to get money out of me, £200 for the battery and £90 registering, won't register a battery I supply

Dan

Its so simple as stated earlier in PM supply a battery providing it's on the money and the Bosch S4/5 stuff will be fine I'll get it registered for you......end of.

Re the BMW spec you'll discover that thryll be various battery options tied to the chassis spec of yiur car, if you look at the diag print I gave you the other day on the last page where it lists the stars build spec you'll see the battery nominated it was from memory a 90aH but can't remember spec, but it'll be on there

[makkan00]

Originally Posted by Dan-

Yeah the issue I'm having, bmw are adamant it's 90ah AGM but how do I know there not just trying to get money out of me, £200 for the battery and £90 registering, won't register a battery I supply

Dan

335d will have 90Ah battery.
What year is your car?
From late 2007 onward bmw started using agm batteries.

Also, my question to you would be why are you changing your current battery?

What issues are you having?

100Ah is defo waste of time and money.

[Dan-]

Originally Posted by makkan00

335d will have 90Ah battery.
What year is your car?
From late 2007 onward bmw started using agm batteries.

Also, my question to you would be why are you changing your current battery?

What issues are you having?

100Ah is defo waste of time and money.

Thanks for the reply, My car is April 2008

Im changing because I'm have trouble starting the car, if left for a few days will struggle to start the car, resets my time and date on the cluster.

[old grey steve]

Originally Posted by Dan-

Thanks for the reply, My car is April 2008

Im changing because I'm have trouble starting the car, if left for a few days will struggle to start the car, resets my time and date on the cluster.

Then you could also have an IBS unit fault too where on occasions it's closing down certain control units to preserve power as well.

[Dan-]

Originally Posted by old grey steve

Then you could also have an IBS unit fault too where on occasions it's closing down certain control units to preserve power as well.

would that not have shown up as a saved fault on Tuesday?

[old grey steve]

Originally Posted by Dan-

would that not have shown up as a saved fault on Tuesday?

Oddly enough you'd think it would but sometimes it doesn't, don't know why which is why when someone volunteers info like losing clock/radio data then you know historically there could well be an IBS issue too as it has the ability at will with no warning to close down control units as/when it sees fit to conserve power.

Drives us mad on occasions Dan, but that's why when cars are booked in info experiences relayed to us are vital as it doesn't always show via diagnostic

[makkan00]

Originally Posted by old grey steve

Oddly enough you'd think it would but sometimes it doesn't, don't know why which is why when someone volunteers info like losing clock/radio data then you know historically there could well be an IBS issue too as it has the ability at will with no warning to close down control units as/when it sees fit to conserve power.

Drives us mad on occasions Dan, but that's why when cars are booked in info experiences relayed to us are vital as it doesn't always show via diagnostic

+1

I think OP should check the health of the battery first.
If battery is fine and healthy then IBS. If battery is poor, then change that first and then IBS.

[old grey steve]

Originally Posted by makkan00

+1

I think OP should check the health of the battery first.
If battery is fine and healthy then IBS. If battery is poor, then change that first and then IBS.

Oddly enough via diagnostic test nothing sinister showed up, if it did I'd of been on it like a rash, but still maintain battery's are good on these cars for around 4 years tops before odd things start to happen, IBS, well know to us and can cause many garages much head scratching as they've not got the insight to factor this in but its a vital component re power management.

Battery supply's power as we know so plan is fit'n'code and get some miles under the cars belt perhaps everything will be OK, but if there's an IBS related fault lurking in the background(and age of car wise they are known for IBS failure-hence BMW have modified the IBS cable and associated parts)then replacing this as you say Sam is the logical next step forward as if its going to tip over the edge it will do it around now.

[old grey steve]

Well battery fitted / coded, we'll hopefully not have any other issues(as you saw today Dan I had another customer walk in with a battery power related issue on my hands)during your time there, plus Kuben was having his hydro unit sortedout for a second time today after again having a battery issue on the first attempt.

So message is see a battery sign appear on the dash, don't ignore it the Infoseek in front of you, change it(battery IMO from new is good for about 4 years before things appear to start playing up)

If you have a battery issue thst results in a flat battery if you have to get power to the car do so from under the bonnet not the rear compartment where the battery is. And if in doubt get the car recovered to a place that can fit'n'code the battery for you, thus reducing the risk of component/module damage.

[Shaun_1990]

sorry if this is a silly question & sorry to OP for asking this but why do you need to register something changing a battery? sorry if its a silly answer but every time in the past it's been one out one in & have changed from old e9x

SHAUN

[Sensible_]

Originally Posted by Shaun_1990

sorry if this is a silly question & sorry to OP for asking this but why do you need to register something changing a battery? sorry if its a silly answer but every time in the past it's been one out one in & have changed from old e9x

SHAUN

See here: http://www.e90post.com/forums/showthread.php?t=621420

You aren't the first to ask and won't be the last!

[old grey steve]

Originally Posted by Shaun_1990

sorry if this is a silly question & sorry to OP for asking this but why do you need to register something changing a battery? sorry if its a silly answer but every time in the past it's been one out one in & have changed from old e9x

SHAUN

We get asked this all the time car conditions it's self and as time goes by it will lose its efficiency then the car may well react accordingly shutting down control,units accordingly, different customers report different issues but when you see a few you generally get to know the similarities,

In a nut she'll when the battery is tied it needs replacing, the car needs to be told there's a new power suppy on board and this will allow the cars systems to be fully reset to accept the costs new battery. As ive said elsewhere if you don't tell the car it's got a new battery it won't gel everything together and this is where you can quite easily get other issues.