[batlin]

Hello,
Thursday at work, I got back to the parking lot after lunch and went into the office. I had to go run a quick errand so about 30 min later I ran out to the car, hit the start button and all electricals came on but car didn't start. I got a buddy to give me a jump and it fired right up. I then drove it home so that I wouldn't be stranded.

I got home threw my trickle charger on it and after a few hours the charger indicated 80% and then overnight it indicated fully charged. It starts up just fine now but I am a tad worried that it may die on me again (I will be keeping jumper cables in the car)

Battery Voltage Last night after it being fully charged (using a volt meter on the battery) 12.4v
Battery Voltage this morning on the Battery after sitting for 12 hours 12.1v

I found the hidden menu and it showed my voltage without the car started at 12.2v and when i started the car it went down to 8.4v for a split second and then came back up to 14.0v

I have heard if the battery goes below 9v on startup you have a bad battery. Is this the case?
As I am getting 14.0v at idle it sounds as if my alternator is fine.
There are no warning lights, I never got a low battery charge light, no flickering lights.

Thoughts?

2011 X3 35, I am not sure if it is original battery, I have owned it for 3 years and it has not had a new battery in that time.

[batlin]

Went to Autozone, tech there said the alternator passed, battery passed but the starter showed an error.

Got home, used my BT cable and did not see anything in regards to starter but saw a lot of under voltages

Short Test

Digital Engine Electronics

Current Fault Codes
CD9437:
DSC, FlexRay: Communications fault

213A21:
Vehicle voltage: Voltage too low


Footwell module

Current Fault Codes
800FB9:
Outside mirror, undervoltage

800F3D:
Output, fog lights, right, short-circuited

800F92:
Welcome light, repeat interlock, active



Central Gateway Module

Current Fault Codes
801C15:
Fault is stored

801C06:
Fault is stored

801C20:
ZGM: central fault memory full - no control-module fault



Junction-box electronics

Current Fault Codes
C90C96:
Electrochromic interior mirror: internal fault

802102:
JBE: undervoltage





Integrated chassis management

Current Fault Codes
48279B:
ICM: Undervoltage in vehicle.




Function Center, Roof

Current Fault Codes
801A4C:
SINE: undervoltage detected in internal voltage supply



High Beam Assist

Current Fault Codes
E0C414:
FLA, K-CAN: communication fault



Combox emergency call


No Faults Found



Car Information Computer

Current Fault Codes
E1C440:
Fault is stored in memory but is not currently occuring






Seat module, driver

Current Fault Codes
8029D4:
SMFA: Undervoltage detected



Trailer module

Current Fault Codes
802819:
AHM: Terminal 30F_B: Voltage supply missing/disruptedFault is stored in memory but is not currently occuring

80281B:
AHM: undervoltage (terminal 30F_B)Fault is stored in memory but is not currently occuring

802837:
Tail light, deactivation due to undervoltageFault is stored in memory but is not currently occuring

[Scout10]

Sounds to me like you have the culprit in sight... bat
What is the name on the battery thats in it??? or p/n

[batlin]

Originally Posted by Scout10

Sounds to me like you have the culprit in sight... bat
What is the name on the battery thats in it??? or p/n

Hi Scout, Thanks for the reply

Battery shows BMW 12V 90Ah 900A
160 RC 900CCA
158 558-10 US

If this is a battery issue, why would Autozones tester say the battery was good and that I had a starter issue?

Thank you!!

[Lurcher]

If the battery is 4+ years old, consider it preventative maintenance. There will be a date code (birthday) stamped into the battery somewhere (month/yr) - All BMWs now are very sensitive to low batteries due to the electronics, and they toss multiple weird/random codes when it goes out.

The battery test assumes it can put on a XX% load and the vehicle will start, BMW electronics could look for a minimum XX+1 %...

Go get http://www.mycarly.com/product/bmw-app/ and register the new battery. Or if you swing by Plano (North Dallas), I'll do it for you...

[Scout10]

Isn't there also a way to date the battery by the p/n or s/n
he posted?

I'd have to say its not the original...... but miracles do happen !

[Sylverlee]

Was this ever resolved? I just ran into the same issue, and I even charged the battery over night the other day on the CTEK (although did it directly to the trunk), doing it now from under the hood. I'm running a AutoCraft Platinum AGM Battery, Group Size H8, 900 CCA.

[Opie55]

Originally Posted by Sylverlee

Was this ever resolved? I just ran into the same issue, and I even charged the battery over night the other day on the CTEK (although did it directly to the trunk), doing it now from under the hood. I'm running a AutoCraft Platinum AGM Battery, Group Size H8, 900 CCA.

Not clear what you mean by "same issue" since the OP gave a number of details. My only comment on his situation is that 12.1 volts on a resting battery that was just charged a few hours earlier is too low. The battery is nominally a 12 volt battery, but a healthy battery at rest should be 12.7 or so.

[richardodn]

Here's a convenient chart on battery voltages and charge levels. https://www.energymatters.com.au/com...age-discharge/

As Opie55 stated, 12.1V on a recently charged battery is way too low. Either the battery is dying or there is excessive draw on the battery when the car is off. For example if the car never goes to "sleep," you'll be discharging your battery much more quickly.