doubledawg33
Posts: 2
Joined: Sat May 30, 2020 4:52 pm

Replaced my 12v battery, now showing "drive-train" fault detected

Sun May 31, 2020 12:37 pm

Woke up yesterday and the 12V accessories battery was dead dead.
Nothing worked.
So I disabled the High Voltage system and removed the old 12V battery.
Measured below 10V.
Figured it's an old battery and needed replacing, so took a trip to my local BMW dealer and picked up a new OEM replacement battery.
Installed the new battery, then I reconnected the High Voltage system.
Everything came back to life. Yay!
I can do everything EXCEPT drive. Check engine light is on and it's showing a Drive Train fault detected message.
Won't let me put the vehicle into gear.

Ordered myself an ODM tool so I can use BImmercode to check the codes. It arrives tomorrow.

In the mean time, just curious if anyone has any thoughts on additional troubleshooting I could try?

Thanks in advance!

alohart
Posts: 2044
Joined: Sat Nov 01, 2014 7:36 pm
Location: Honolulu, HI

Re: Replaced my 12v battery, now showing "drive-train" fault detected

Sun May 31, 2020 9:07 pm

doubledawg33 wrote:
Sun May 31, 2020 12:37 pm
I can do everything EXCEPT drive. Check engine light is on and it's showing a Drive Train fault detected message.
Won't let me put the vehicle into gear.

Ordered myself an ODM tool so I can use BImmercode to check the codes. It arrives tomorrow.

In the mean time, just curious if anyone has any thoughts on additional troubleshooting I could try?
If you're lucky, your i3 will reset itself overnight.

If not, you might need to license BimmerLink which should work with your OBD dongle. BimmerLink should allow you to delete any diagnostic trouble codes (DTC's) that might be preventing your i3 from being drivable.

An extra bonus would be the ability to register your new 12 V battery. However, not having registered your new battery isn't the reason that your car isn't drivable. Registration would record the date that the new battery was installed which could help a future mechanic. There's no evidence that registration helps the charging system charge the 12 V battery more optimally as it ages which apparently is true with ICE BMW's.

Please let us know the solution. I may be replacing the 12 V battery in our 2014 i3 one of these days, so it would be nice to avoid the problem you're having.
Aloha,
Art

2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE

User avatar
MKH
Gold Member
Posts: 584
Joined: Fri Nov 02, 2018 5:48 am
Location: Dallas

Re: Replaced my 12v battery, now showing "drive-train" fault detected

Mon Jun 01, 2020 11:47 am

I have an OEM i3 battery, purchased from the local East Penn warehouse sitting on a shelf, for use when the original one in my 2015 shows signs of end-of-life. It shows 12.3 volts, 58% SOC, and a"Good - Recharge" message - so appears the first step in swapping out a battery, is make sure the new one going in is fully charged.

I used this to check the battery.

https://www.amazon.com/gp/product/B07ZT ... UTF8&psc=1
Mark H.
2015 i3 Rex, Capparis White, Tera World, Technology & Driving Assistant, Parking Assistant, Harman Kardon Audio System, 19 inch 427 wheels, EVoInnovate EVSE

doubledawg33
Posts: 2
Joined: Sat May 30, 2020 4:52 pm

Re: Replaced my 12v battery, now showing "drive-train" fault detected

Mon Jun 01, 2020 8:38 pm

All seems to be OK for now. Here's what I did:
- Deactivated the High Voltage.
- Removed the new battery and put it on the trickle charger overnight.
- Reinstalled the new battery.
- Reactivated the High Voltage.
- Jumped into the cockpit, plugged in the ODB.
- Turned on Accessories. Accessories only stayed on for 10seconds. All kinds of lights and warnings and then it would shut itself off.
- Every time I turned on Accessories, the same thing would happen.
- I figured since the 12V had been off for so long, all the electronics were in wonky error states and so nothing was talking to anything.
- Anyways, fired up BimmerLink and then turned on Accessories again and quickly started pulling codes - there was a bunch. Everytime accessories would shut off, I'd turn it back on and keep pulling codes.
- Once all the codes were pulled, I started clearing them - same deal, had to keep turning on Accessories again and again every time it turned itself off.
- Repeated this process for 10minutes and slowly things started coming back.
- Eventually the Accessories remained on.
- I kept pulling codes and clearing codes.
- Then it was like everything was happy.
- Happy to report it's 100% now. No check engine light, no drive train errors or other errors poping up on the instrument cluster.

Took it for a 20 minute test drive, no issues. Started up the Rex using the emissions sequence and let that run for a while - again all good there.

And lastly registered the new battery which seemed anti-climatic given everything else I had gone through.

So I chalk all of my symptoms up to what happens when the 12V battery dies.

I'll report back how things look over the next few days.

Hope this is helpful to someone out there.

Bertone
Posts: 16
Joined: Wed Jan 22, 2020 9:37 am
Location: Madrid, Spain

Re: Replaced my 12v battery, now showing "drive-train" fault detected

Wed Jun 03, 2020 3:31 am

Glad you fixed the problem.... that was really a scary one!!!!

Is there a way to know the health of the 12v battery with bimmerlink or entering the car's dash hidden menu?
2017 94Ah

eNate
Posts: 427
Joined: Mon Sep 09, 2019 5:33 pm

Re: Replaced my 12v battery, now showing "drive-train" fault detected

Wed Jun 03, 2020 10:58 am

Bertone wrote:
Wed Jun 03, 2020 3:31 am

Is there a way to know the health of the 12v battery with bimmerlink or entering the car's dash hidden menu?


You must mean a way to see the the same data the system generates as it monitors the 12v battery's health over its lifespan, so as to continually adjust the charging parameters to optimize its longevity -- the foundational purpose behind BMW battery registration process!

Yeah... no.

...because it doesn't do that.

https://youtu.be/kMxdFwCU1OE
2 0 1 7   B M W   i 3   9 4 A h   B E V  O a k l a n d
 Wokeby Trunk Extension | Duosida 16A L1 EVSE
 SeaSucker Monkey Bar Roof Rack

Return to “Problems / Troubleshooting”