M54B30

This warning came up to idrive screen sometimes. I did not take much notice since the car started everytime. Though once i had the key halfturn and listen radio for a few minutes than the car did not start.

Car was at garage for 3days. So the car did not start. Light are little weak.

Do you think there is a short cut in the electric system or simply battery replacement needed ?

Previous owner had told me the battery was ok but not suit the car somehow. Did he have a point?

The battery 95 amper. Varta brand.

BostonJon

could be a bad battery, a battery that wasnt registered (or not registered properly), an open circuit somewhere causing drain, etc. what have you tried so far?

M54B30

Not tried anything
How not registered battery could cause this problem ? It prevents go in to sleep mode etc ?

Since i am not very familiar with the car, i plan to go my electrician.

If no car around for a help, how do you start up the car if the car is not starting when just lights are alive ?
Is there a tool for that ?

BostonJon

my understanding is that if the battery is not registered properly, the car cannot charge and monitor it properly.

if you dont have jumper cables or someone around to help you, you could use something like this:

M54B30

Thank you.
Battery registration is a DIY job or need to go to bmw service ?

What capacity do i need for my bimmer for that jump starter ?

I will hopefully visit USA very soon so i can buy it from there.

M54B30

Hi,

In relation with this warning, i got the car checked. No short circuit found that might drain the power at sleep mode. The battery is 90mAh one and shows 12V exactly when the car is not running. I stated the engine the electrician guy told me the battery is not too bad and might still keep it. The battery is registered with the car.

So if i change the battery, do you think 90mAh is enough? Or i should go for 100mAh one ?

My car specs are;
M54B30
2005 year
Extras;
HUD
Recaro seats with memory
Hi-fi (logic7)
Active steering
Wide idrive screen
Sunroof
Adaptive headlights
Bixenon

Thanx for your help !

DanielFD

Well BMW's battery is a 90mah battery but putting a 100mah isn't a bad idea. also if you want an upgrade go with AGM batteries, much better technology. but i'm not sure this will solve your discharge problem, might need some deeper diagnosis.

M54B30

Thank you.
I just called the dealer. DMA 's twice as expensive. 390eur plus servicing. I check the battery voltage figure this afternoon before starting the car after 1.5 days parked at my garage. Showed 11.8 V figure down from 12.0 V. figure compared to 1,5 days previous figure.

I believe there is no short circuit/drain. Is it normal ???

M54B30

Today i drove an hour and covered roughly 25km (18miles). Then i checked the battery when engine running, my voltmeter toll showed 14V. That means my alternator ( battery charging unit) is working. When stopped the engine, it dropped to 12V. As far as i know for an healthy battery it must show at least 12.4V min. That i learned from a youtube video if correct.

When car is parked for 36hours, it would dropped to 11.8V. Do you think 0.2V drop within 36 hours normal?
My bmw garage found no short circuit or IBS issue that might drain the battery during sleep mode but i already experienced my car did not started when parked for 72hours. However he did not blame the battery since he thinks it is still ok.

Could you please share your opinion with me for a possible solution and what additional disgnosis should i do ?

I do not know very reliant people in my area, since some other car stores try to sell a battery to me and i do not want to do trial and error method by replacing the battery if it is still ok.

I must appreaciate your help.

Emre

DanielFD

thats a very small change in voltage, and also voltage drops the father away you are. so if your testing from the engine bay then thats spot on. To be honest there is no way to tell for sure if its a drain or not without testing for a couple days. how old is your battery? if its over 3-4 years then consider battery replacement as preventative maintenance. Also, you dont need to buy the battery from the dealer. Good brand with the right CCA and mah will do fine.