[Orange fever]

Damnnn I have 8 years... Oem and my car has all the goodies after to break in, Vf tune stg 2 , downpipe, intercooler. ( Knock on what now) Lol

[vrooooom]

How would one know the state of my AGM battery? 50% or 30% left?

6+ yrs now....

[vrooooom]

Originally Posted by F87source

Depending on how often you drive it and if you store it with a tender generally batteries last from 5-10 years. Mine is going on 6 years without issue, it can sit for multiple weeks without driving and still not show any low battery warnings. I believe the total capacity check said it was in the 78-80% range, so mine should be ok for another few years.

Yes you must program the car (this process is called battery registration) when you replace it with a new battery. This is because the car's IBS progressively charges the battery less and less as capacity decreases with age. So if you do not register the new battery the car will under charge it and that will cause the battery to degrade and lose its peak capacity even faster.

How did you check this "total capacity" F87?

I didn't know that the car charges less as the battery age. Good to know. But since we usually charge it externally on our own (CTEK, Noco etc) anyways, it somewhat circumvents that.

[F87source]

Originally Posted by vrooooom

How did you check this "total capacity" F87?

I didn't know that the car charges less as the battery age. Good to know. But since we usually charge it externally on our own (CTEK, Noco etc) anyways, it somewhat circumvents that.

You can view the battery capacity percentage using ista, bimmerlink, and im pretty sure protool (although I haven't tried it on protool yet). im pretty sure this is a measure of effective capacity - how much it currently holds vs. true potential.


No not really. As a battery ages it won't be able to accept the same amount of charge as when it was new - so effective capacity still decreases. The ibs just helps the car not over charge the battery when it gets old. So what this means is if your battery is getting old, no charge will save it, it isn't a matter of charging it more.

[TMR013]

3 years. I live in AZ which is notoriously hard on batteries. My old 135 made it to 5 years.