[BobsM3Coupe]

If say for example, I wanted to remove the steering wheel airbag.
I know I need to disconnect the large vehicle negative battery under the rear cargo area, but what about the smaller auxiliary battery under the hood on the passenger side at the back of the engine compartment?

[Alan l.]

No need. I've done it on my X5M swapping the paddles and just doing the rear battery was enough.

[WellsX5]

Do you lose all the programming in the computer when disconnecting the battery?
Wondering as I need to replace an amp this weekend and debating disconnecting the battery or not.

[BobsM3Coupe]

Originally Posted by Alan l.

No need. I've done it on my X5M swapping the paddles and just doing the rear battery was enough.

Good to know. Thank you. Though I had a trim piece on the steering wheel replaced (creaking noise) by the dealer and it looks like he may have turned off battery power by the small auxiliary battery under the hood. Or something in that same compartment. I know he didn't disconnect the main battery in the rear. Hmm?

[JimVR4]

Originally Posted by WellsX5

Do you lose all the programming in the computer when disconnecting the battery?
Wondering as I need to replace an amp this weekend and debating disconnecting the battery or not.

It's basically the same as rebooting iDrive. You might have to operate the tailgate a couple times to get it to sync up after reconnecting.

[Alan l.]

Originally Posted by WellsX5

Do you lose all the programming in the computer when disconnecting the battery?
Wondering as I need to replace an amp this weekend and debating disconnecting the battery or not.

Disconnecting the battery in the trunk didn't wipe out anything in my case and I probably had it unplugged for a good hour.

Alan

[Qsilver7]

Check your owners manual...the sunroof may need a reset after a battery nap (loss of power). And on some BMW models the one-touch windows, clock, and date may need a reset after a battery nap. But it also may depend on how long the cable is disconnected.

Also, if you do have an aux battery...if you disconnect the main battery...the vehicle is NOT totally de-energized according to the TIS. So do be careful when disconnecting airbag and SRS/MRS electrical connections if you haven't disconnected both batteries....there is a risk of shorting if you leave the aux battery attached. So just be careful & aware of the risk.

[julioccuk]

I am trying to swap my paddle shifters for carbon ones. The job itself is fairly easy to perform according to videos I’ve seen online.

Basically you disconnect the negative terminal from the trunk battery and that should allow you to remove the center block of the steering wheel and get them changed.

The issue for me is that the new G06 LCI comes with the BMW MHEV technology and by disconnecting the negative cable in the trunk alone didn’t seem to have powered off the steering wheel as the horn was still working so I didn't proceed worrying I could set the airbag off.

Wondering if anyone can guide me through how to disengage the airbag to carry out the job?

Thanks in advance

[Marty in NY]

Originally Posted by julioccuk

I am trying to swap my paddle shifters for carbon ones. The job itself is fairly easy to perform according to videos I’ve seen online.

Basically you disconnect the negative terminal from the trunk battery and that should allow you to remove the center block of the steering wheel and get them changed.

The issue for me is that the new G06 LCI comes with the BMW MHEV technology and by disconnecting the negative cable in the trunk alone didn’t seem to have powered off the steering wheel as the horn was still working so I didn't proceed worrying I could set the airbag off.

Wondering if anyone can guide me through how to disengage the airbag to carry out the job?

Thanks in advance

For a pre LCI MHEV with the 48 v Li-on battery: I can't speak to the airbag but once you open the engine hood/bonnet, that automatically disconnects the Li-on battery but to be sure, once you have the hood open, get in the car with your key fob and press the start button three times in succession quickly without your foot on the brake. You should then see a msg in the bottom center of the dash that says your 48v system is disconnected. Once you do that and confirm its disconnected, then you can go in the cargo area/boot and remove the negative terminal from the battery and wrap it in a towel so there's no chance it will fall somewhere and touch ground.

WARNING: Never close the engine hood/bonnet if the rear cargo area battery is still disconnected as this will/may (according to BMW) damage the Li-on battery because closing the engine hood/bonnet will automatically reconnect the Li-on battery back into the electrical circuit.

[julioccuk]

Originally Posted by Marty in NY

For a pre LCI MHEV with the 48 v Li-on battery: I can't speak to the airbag but once you open the engine hood/bonnet, that automatically disconnects the Li-on battery but to be sure, once you have the hood open, get in the car with your key fob and press the start button three times in succession quickly without your foot on the brake. You should then see a msg in the bottom center of the dash that says your 48v system is disconnected. Once you do that and confirm its disconnected, then you can go in the cargo area/boot and remove the negative terminal from the battery and wrap it in a towel so there's no chance it will fall somewhere and touch ground.

Can't thank you enough, so simple and still I would never know. Thank you a lot, got the paddles swapped like a charm.

[Marty in NY]

Originally Posted by julioccuk

Trying in a minute, will let you know. Thanks a lot for now.

WARNING: I forgot to mention this in my last post but.....never close the engine hood/bonnet if the rear cargo area battery is still disconnected as this will/may (according to BMW) damage the Li-on battery because closing the engine hood/bonnet will automatically reconnect the Li-on battery back into the electrical circuit.

[julioccuk]

Originally Posted by Marty in NY

WARNING: I forgot to mention this in my last post but.....never close the engine hood/bonnet if the rear cargo area battery is still disconnected as this will/may (according to BMW) damage the Li-on battery because closing the engine hood/bonnet will automatically reconnect the Li-on battery back into the electrical circuit.

Thanks for that but I figured and left it open the whole time and only closed after the negative terminal was back to its place in the trunk battery. All seems fine and functioning. No warnings.

Thanks a lot again.

[Marty in NY]

Originally Posted by julioccuk

Thanks for that but I figured and left it open the whole time and only closed after the negative terminal was back to its place in the trunk battery. All seems fine and functioning. No warnings.

Thanks a lot again.

Whew!

BTW, I know were Redhill is, I used to live in Maidstone.

[julioccuk]

Originally Posted by Marty in NY

Whew!

BTW, I know were Redhill is, I used to live in Maidstone.

Yeah, it's a lovely little place with great connections to central London and 10 miles from Gatwick which is brilliant.

Been here since 2019 and so far so good.