Battery Light : Confusing Symptoms, new battery

tlow98 · 11-11-2019, 04:03 PM

Hi all.

Pretty sure I need a new battery but hear me out.

Battery:
original, 10 year old 102k mike BMW OE battery

Symptoms:
For the last few years the battery light comes on only when the battery gets drained from playing music or needing the lights while the car is off. Lately, it comes on a couple times a week. Car still starts and runs fine.

Testing:
14.7 volts on my multi meter while the car is on. Good. No alternator needed.
12.1 volts when the car is off and I’m testing
12.4 volts when I pull the battery and bench test. F

Do I have parasitic drag (car ALWAYS starts never needed a jump) or is this thing just shot?

Keep in mind Cali batteries in my area last a long time. Temp always between 50 and 90 degrees out.

Appreciate the sanity check.

lowrydr310 · 11-11-2019, 04:25 PM

Quote:

Originally Posted by tlow98

Battery:
original, 10 year old 102k mike BMW OE battery

Do I have parasitic drag (car ALWAYS starts never needed a jump) or is this thing just shot?

10 years and 100K+ on a battery is a pretty darn good run! Consider yourself lucky. I'd just replace it at that point.

I'm in Southern California and my batteries don't seem last much longer than 5 years. The last one I changed on my Honda was almost 5 years old and was still good but a failed alternator resulted in it discharging compeltely. Intead of charging I just replaced it. My E90 battery is over 7 years old and still holding a charge for now.

lab_rat · 11-11-2019, 05:57 PM

On my first E90, the battery lasted ~10 years/95,000 miles before replacement.

Just be sure to get the correct battery (AGM vs Lead) and correct Ah when replacing.

I tried aftermarket and OEM batteries, and found OEM were best.

YMMV

colorado.e9x · 11-11-2019, 06:41 PM

Quote:

Originally Posted by lab_rat

On my first E90, the battery lasted ~10 years/95,000 miles before replacement.

Just be sure to get the correct battery (AGM vs Lead) and correct Ah when replacing.

I tried aftermarket and OEM batteries, and found OEM were best.

YMMV

Congratulations! That battery has lasted quite a long time compared to some of us in the midwest.

I'd replace it just for piece of mind. If you have it in your area I highly recommend Interstate batteries. Its the only aftermarket battery I'll ever use.

I'm going to have to disagree about what lab_rat said about getting the correct battery. You can get pretty much any battery that's H6,H7 or even H8 which will barely fit. Coding options are available for both flooded and agm, as well as coding the correct aH.

If that's too much work though then yeah match up all the specs

tlow98 · 11-11-2019, 08:05 PM

Yeah, thanks guys.

I don’t have the capability to load test so replaced with the Walmart H8 group 49. Thing is YUGE.

Just need to register - I don’t think I’ll need to code I think it’s the same 90aH I’m replacing but will dig into that later this eve.

lab_rat · 11-11-2019, 08:39 PM

Quote:

Originally Posted by colorado.e9x

Congratulations! That battery has lasted quite a long time compared to some of us in the midwest.

I'd replace it just for piece of mind. If you have it in your area I highly recommend Interstate batteries. Its the only aftermarket battery I'll ever use.

I'm going to have to disagree about what lab_rat said about getting the correct battery. You can get pretty much any battery that's H6,H7 or even H8 which will barely fit. Coding options are available for both flooded and agm, as well as coding the correct aH.

If that's too much work though then yeah match up all the specs

No worries, you are correct - with coding/registering, one can always code for an alternate type and aH. I've read how other's have had success with AGM vs Lead, different aH, etc.

My car didn't like the aftermarket battery, even with coding/registering. But honestly, I possibly could have coded the aftermarket battery wrong. LOL

Thoughts on BMW's use of different battery types and aH:
*Did BMW set up the aH and type based on a specific car's build/option list?

*Could the aH/battery type choices possibly be based on the updates to wiring schematics and/or changes to electrical parts during the E9x platform?

pedro2u · 11-11-2019, 08:40 PM

you should just change the battery now even if you just consider it preventive maintenance. You are well passed it's useful life, and now you're just on borrowed time until the day it leaves you stranded somewhere (and you'll be kicking yourself then for not having changed it now).

Join those of us that got 10 years, claim it a victory, and count your blessings

colorado.e9x · 11-11-2019, 10:04 PM

Quote:

Originally Posted by lab_rat

Quote:

Originally Posted by colorado.e9x

Congratulations! That battery has lasted quite a long time compared to some of us in the midwest.

I'd replace it just for piece of mind. If you have it in your area I highly recommend Interstate batteries. Its the only aftermarket battery I'll ever use.

I'm going to have to disagree about what lab_rat said about getting the correct battery. You can get pretty much any battery that's H6,H7 or even H8 which will barely fit. Coding options are available for both flooded and agm, as well as coding the correct aH.

If that's too much work though then yeah match up all the specs

No worries, you are correct - with coding/registering, one can always code for an alternate type and aH. I've read how other's have had success with AGM vs Lead, different aH, etc.

My car didn't like the aftermarket battery, even with coding/registering. But honestly, I possibly could have coded the aftermarket battery wrong. LOL

Thoughts on BMW's use of different battery types and aH:
*Did BMW set up the aH and type based on a specific car's build/option list?

*Could the aH/battery type choices possibly be based on the updates to wiring schematics and/or changes to electrical parts during the E9x platform?

Completely agree, my battery (still an interstate) must still be weak enough for the amount of power this car consumes in accessory mode. Doesn't help that 99% of my drives are 10-15 minutes either lol

tlow98 · 11-11-2019, 11:17 PM

Quote:

Originally Posted by colorado.e9x

Completely agree, my battery (still an interstate) must still be weak enough for the amount of power this car consumes in accessory mode. Doesn't help that 99% of my drives are 10-15 minutes either lol

Yeah, this is when my car starts to get upset.

colorado.e9x · 11-12-2019, 12:13 AM

Quote:

Originally Posted by tlow98

Quote:

Originally Posted by colorado.e9x

Completely agree, my battery (still an interstate) must still be weak enough for the amount of power this car consumes in accessory mode. Doesn't help that 99% of my drives are 10-15 minutes either lol

Yeah, this is when my car starts to get upset.

Especially in the winter

marvinstockman · 11-12-2019, 08:09 AM

I may be wrong, but if you put the same battery in that you took out, you can avoid getting coded.

pedro2u · 11-12-2019, 09:12 AM

rather than explaining why you need to register the new battery. here's a pretty good explanation:

https://bimmertips.com/bmw-battery-r...ing-explained/

tlow98 · 11-12-2019, 07:30 PM

Quote:

Originally Posted by marvinstockman

I may be wrong, but if you put the same battery in that you took out, you can avoid getting coded.

no biggie. have the software with bimmergeeks ProTool.

e90yyc · 11-13-2019, 12:37 PM

Nice run. I was in disbelief when I changed my original battery after about 170k miles and 10 years. The climate where I live is terrible too... Much respect to IBS, as there’s no way a “dumb-charged” battery would have lasted this long.

I went with OE battery, but only paid about $130 for it so it made sense.

tlow98 · 11-13-2019, 10:15 PM

Quote:

Originally Posted by e90yyc

Nice run. I was in disbelief when I changed my original battery after about 170k miles and 10 years. The climate where I live is terrible too... Much respect to IBS, as there’s no way a “dumb-charged” battery would have lasted this long.

I went with OE battery, but only paid about $130 for it so it made sense.

That’s a good deal. I was looking at $220+ around here for OE. no thanks at that price

Fritzer · 11-13-2019, 10:18 PM

Quote:

Originally Posted by tlow98

original, 10 year old 102k mike BMW OE battery

My OE battery went out at 100k - 7 years. You probably need a new battery.

11-11-2019, 04:03 PM	#1
tlow98 Major General 2188 Rep 5,001 Posts Drives: 2009 E91, 2014 F15 x35i Join Date: Aug 2011 Location: Bay Area iTrader: (2)	Battery Light : Confusing Symptoms, new battery Hi all. Pretty sure I need a new battery but hear me out. Battery: original, 10 year old 102k mike BMW OE battery Symptoms: For the last few years the battery light comes on only when the battery gets drained from playing music or needing the lights while the car is off. Lately, it comes on a couple times a week. Car still starts and runs fine. Testing: 14.7 volts on my multi meter while the car is on. Good. No alternator needed. 12.1 volts when the car is off and I’m testing 12.4 volts when I pull the battery and bench test. F Do I have parasitic drag (car ALWAYS starts never needed a jump) or is this thing just shot? Keep in mind Cali batteries in my area last a long time. Temp always between 50 and 90 degrees out. Appreciate the sanity check.
	Appreciate 0 Tweet Quote

11-11-2019, 08:05 PM	#5
tlow98 Major General 2188 Rep 5,001 Posts Drives: 2009 E91, 2014 F15 x35i Join Date: Aug 2011 Location: Bay Area iTrader: (2)	Yeah, thanks guys. I don’t have the capability to load test so replaced with the Walmart H8 group 49. Thing is YUGE. Just need to register - I don’t think I’ll need to code I think it’s the same 90aH I’m replacing but will dig into that later this eve.
	Appreciate 0 Quote

11-11-2019, 08:40 PM	#7
pedro2u Lieutenant 278 Rep 443 Posts Drives: '11 E93 M3 6MT, '08 E92 335Xi Join Date: Jan 2019 Location: Southington, CT iTrader: (0) Garage List 2008 BMW 335XI E92 [0.00] 2011 BMW M3 E93 [0.00]	you should just change the battery now even if you just consider it preventive maintenance. You are well passed it's useful life, and now you're just on borrowed time until the day it leaves you stranded somewhere (and you'll be kicking yourself then for not having changed it now). Join those of us that got 10 years, claim it a victory, and count your blessings __________________ Pete
	Appreciate 0 Quote

11-12-2019, 08:09 AM	#11
marvinstockman Major 399 Rep 1,077 Posts Drives: 2011 BMW 328i Join Date: Aug 2015 Location: Rockville, MD iTrader: (0)	I may be wrong, but if you put the same battery in that you took out, you can avoid getting coded.
	Appreciate 0 Quote

11-12-2019, 09:12 AM	#12
pedro2u Lieutenant 278 Rep 443 Posts Drives: '11 E93 M3 6MT, '08 E92 335Xi Join Date: Jan 2019 Location: Southington, CT iTrader: (0) Garage List 2008 BMW 335XI E92 [0.00] 2011 BMW M3 E93 [0.00]	rather than explaining why you need to register the new battery. here's a pretty good explanation: https://bimmertips.com/bmw-battery-r...ing-explained/ __________________ Pete
	Appreciate 0 Quote

11-13-2019, 12:37 PM	#14
e90yyc Art Collector 2425 Rep 3,448 Posts Drives: 2007 328xi (GM-delete 6MT) Join Date: Feb 2018 Location: Canada iTrader: (0)	Nice run. I was in disbelief when I changed my original battery after about 170k miles and 10 years. The climate where I live is terrible too... Much respect to IBS, as there’s no way a “dumb-charged” battery would have lasted this long. I went with OE battery, but only paid about $130 for it so it made sense. __________________ When I'm dead, just throw me in the trash.
	Appreciate 0 Quote