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Discussion Starter #1
Hi

I have an issue with the airbag lamp on my car.
I had some trouble with the heating mat in the front driver's seat and took the whole seat out of the car to get it fixed. Long story short, I had to unplug the wires from the seat while the battery was connected. I knew it would trigger the airbag lamp, but I had no other choice.

Took it to two different shops that tried to reset the airbag lamp, but they couldn't even enter the airbag category. They confirmed that the tools usually was able to do it on BMW.

So I have tried different stuff like, disconnecting the battery and letting it stay overnight before plugging it in. Also unplugging the seat connectors and fuses. all with no luck. The lamp still returns when fuses are back in and the seat is connected.
I am confident that this has nothing to do with the occupancy sensors as it was triggered by the fact that I removed the seat as I explained.

So I noticed that fuse nr 40 is both listed under airbag and instrument cluster. Tried to remove it and the lamp finally stopped. nothing happened when I removed fuse 42 which is only listed under airbag.

So the question is, does anyone know how to fix this? And can I just remove fuse 40 to avoid the annoying lamp? or will this cause the airbag to not deploy if Icrash?

Thank you in advance!
 

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If you use the newtis.info website...you can look up fuse 40 (F40) and see exactly what it powers.

I entered generically for an e39 528i...then typed "F40" into the search box...and it pulls up this wiring schematic: https://www.newtis.info/tisv2/a/en/e39-528i-lim/pe27Fh8

When you look at the wiring schematic...you'll see that it controls the electronic seat control (A113)...and instrument cluster (A2)....and the mat sensor (I01009) The things in the schematic that are in blue text are clickable links that will take you to additional information. If you click on those links you'll see that there is information for PIB (pin out information)...and if you go to those....you can see what is powered by fuse 40 in the instrument cluster and electronic seat control...and those things may be what is causing rejection of SRS reset.

If you pull fuse 40...then those things will no longer be powered.

In regards to the air bag light...if you are trying to reset the light and the SRS (supplemental restraint) warning light won't reset...then that is an indication that something in the system has not been repaired...thus the light won't reset. You may need to check and recheck the seat connections and the control module to see why after reconnecting the electrical connections are not resetting when you connect to SRS to do a reset.

Good luck.
 

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Discussion Starter #4
Thank you @Qsilver7.

I'll try to clean the connectors with some electrical cleaner spray.

It's just so strange that something suddenly is "broken" when all I have done is remove the seat and reinstalling it again.

I am not really that familiar with electronics and wiring diagrams. But I now see that fuse 40 also powers the electronic seat control.

Hopefully the cleaner will help, or else I am lost.
 

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Where are you located? If you are near NJ I’d read the code for you.


Sent from my iPhone using Tapatalk
 

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Wingnut
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Hi
I knew it would trigger the airbag lamp, but I had no other choice.
btw, you do have another choice, when working with any of the airbags, the rest of the SRS system, and other electrical repairs. disconnect the - battery cable. no airbag/srs lite will be set.
 

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Discussion Starter #8
btw, you do have another choice, when working with any of the airbags, the rest of the SRS system, and other electrical repairs. disconnect the - battery cable. no airbag/srs lite will be set.
Yes, I am aware of that. But as I said, I had no other choice to do it that way.
 

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Discussion Starter #9
Thanks again..

I decided to go to the official BMW shop where I live and they hooked it up to INPA and got the SRS lamp deleted.
No faults with the system. So thankfully its gone now.

The other shops I went to first didn't have the correct obviously!
 
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