Airbag Warning Light stays on

Marco

Member
 Hampshire
The Airbag light stayed on a few days ago. I have done a search and read through a lot of posts on this forum about this issue (some are quite old) and it appears to me that it is a rather unknown entity and ultimately you need BMW to diagnose the fault. It also appears that most of the Posts on the Forum have been from 2003/2004 Z4 owners experiencing this issue – wondering if this issue is prevalent in cars manufactured in those years?

Anyway I went to my local dealer today and they said I would need to book it in for a 1 hour appointment, so it would cost £132 just to diagnose the fault and then whatever the cost may be to repair it. He also said many times they just reset it under the seat and it goes away but sometimes it comes back on again after a few days (they won’t guarantee it) and so I would be back at “square one”, having to pay for another diagnosis, and if nothing is identified, they may just suggest changing a part not knowing if that is the actual cause of the fault …..but that the choice would be mine. I find this a little odd, they charge you to diagnose it and then may not be able to diagnose it properly and may have to just start changing random (but related) parts? Needless to say this does not really fill me with confidence.

I noticed from previous posts that the airbag seat sensor (that detects the amount of weight in the passenger seat) is a common failure, and I believe from some posts that BMW (in USA) have acknowledged this as a fault and extended the warranty on that item. Does anyone know if the same applies in the UK?

Also, has anyone had this issue and tried “re-setting” this connection under the seat/s, if so, is it easily identifiable and done?

Thanks!
 
You can reset the error with the right cable and software but if the problem is still there then it will come back on again. Likewise you can pay BMW lots of money to reset it but again it may come back on.

It does seem that it is a *known issue* in the USA but BMW UK claim not to have heard of it (or just don't give a s**t).

Mine was on because (I think) a bottle rolled under the seat and the seat was sat on. I removed the bottle, reset the light and it's not been on since. I recon I was lucky.
 
I bought my Z about 6 months ago, it had an airbag light on when I drove it off. Depending on what it is, its a piece of piss to reset. Any OBD reader should be able to reset it, if it comes back on it needs investigating further. But mine was reset by my indy when it was in for a service for no charge. I got my E46 airbag light reset by my local garage when it was in for its MOT, no charge. So for BMW to say they want £132 for it. GFY is what I would say :P
 
Marco said:
Thanks! Quick question....How did you reset the light?

I used the INPA software and a cable off ebay. Some people have success and some don't, depends on whether the problem still exists I guess.
 
If anyone is interested in how the Safety System (Airbags) is configured and how/when they deploy, take a look at this document (seems to be quite informative):
http://www.freefilehosting.net/09e85advsafetyelectronics
 
I did what may have been a mistake, but I jump started my 2003 Z4 and the airbag light has come on.

The reason I had to jump start the car was because the alarm keeps going off which I have searched for and believe the most likely cause is the bonnet sensor?

Could I have done some damage when jump staring the car? Any help would be much appreciated.
 
I noticed from previous posts that the airbag seat sensor (that detects the amount of weight in the passenger seat) is a common failure

I take this is to prevent airbag operation of the seat is empty?

May not always work but disconnecting the battery can often extinguish the light.
 
Marco said:
If anyone is interested in how the Safety System (Airbags) is configured and how/when they deploy, take a look at this document (seems to be quite informative):
http://www.freefilehosting.net/09e85advsafetyelectronics
WOW ! Thanks Marco for that link.
There has always been different views about whether or not the airbag will deploy if the seat pressure mat is defective.
Now we have it clearly stated on page 19 of the official BMW training document :
"If a fault is detected in the seat occupation detection system, it is assumed that the seat is occupied. The restraint systems are activated"
My wife and myself have been touring round all summer with the damn lights on very worried as two dealers told us the the passenger airbag will not activate in the event of a crash.
These aystems are very sophistcated probably beyond the understanding of many dealers maybe.
Like others my lights came on after an attempted jump start.
My local indy, who may or may not be trustworthy, has quoted me $780 for fitting a new mat/cushion (I live in the USA). I guess the main BMW dealer would probably want $1500 for the same work !
I've got a diagnostic cable with INPA installed but can't seem to turn the lights off. Anybody know exactly how to do it ?
The pressure mat comes integrated with a cushion and the price here from an independent parts supplier (getbmwparts) is $420.38, the part no being 52109144002 for black leather.
Anybody fitted a new mat/cushion? Detailed guide would be very much appreciated.
Here in USA BMW have replaced mats free for Z4s up to 2005. MIne is 2006 ! Apparantly in 2006 the mat design was changed with an integral black box module. More reliable ?? :lol:
 
I would appreciate clarification on the Z4 airbag indicator lights...there are two of them

My Airbag light on the right side of the console is illuminated when I am alone and extinguished when I carry a passenger. Is this a normal situation or should it be extinguished? The light in the dash is not illuminated so I figure there is no significant issue with the system but the illuminated light on the console is annoying...luckily most of my night driving is with a passenger.

I have searched threads and the various posts have totally confused me as to what is normal for driving without a passenger in the seat...on or off?

If I sit in the passenger seat and turn on the key the console airbag light illuminates for a few seconds and then goes out. If I sit in the drivers seat it stays on. If I use my key to disable it then it stays off but then I would have to remember to turn it back on when carrying a passenger...this is not safe IMHO.

Since none of my other vehicles have had an airbag light illuminated as a normal driving situation I am concerned that there is something wrong. Was the BMW system designed to be illuminated when the seat is unoccupied? Anyone know the correct answer?

Thanks
 
If I remember correctly that's linked to the baby seat kit (isofix?). I think the light is to remind you that the airbag is activated because there is a passenger sat there. i.e. if you had a baby-human in there you'd want to de-activate it so as not to squish them.
 
Stromtech said:
I would appreciate clarification on the Z4 airbag indicator lights...there are two of them

My Airbag light on the right side of the console is illuminated when I am alone and extinguished when I carry a passenger. Is this a normal situation or should it be extinguished? The light in the dash is not illuminated so I figure there is no significant issue with the system but the illuminated light on the console is annoying...luckily most of my night driving is with a passenger.

I have searched threads and the various posts have totally confused me as to what is normal for driving without a passenger in the seat...on or off?

If I sit in the passenger seat and turn on the key the console airbag light illuminates for a few seconds and then goes out. If I sit in the drivers seat it stays on. If I use my key to disable it then it stays off but then I would have to remember to turn it back on when carrying a passenger...this is not safe IMHO.

Since none of my other vehicles have had an airbag light illuminated as a normal driving situation I am concerned that there is something wrong. Was the BMW system designed to be illuminated when the seat is unoccupied? Anyone know the correct answer?

Thanks
The console light should only come on when you have deliberately de-actvated the passenge restraint system (which includes the passenger airbag) by turning your ignition key to the appropriate postion in the keyhole at the end of the dash (and removing the key after of course).
If you have set the "passenger airbag enabled" setting with your key then the console light should never be permanently on.
Seems like you may have a glitch in the electronics somewhere. Try and get an Indy to reset it but don't go to a dealer!
 
mikebeesley said:
Stromtech said:
I would appreciate clarification on the Z4 airbag indicator lights...there are two of them

My Airbag light on the right side of the console is illuminated when I am alone and extinguished when I carry a passenger. Is this a normal situation or should it be extinguished? The light in the dash is not illuminated so I figure there is no significant issue with the system but the illuminated light on the console is annoying...luckily most of my night driving is with a passenger.

I have searched threads and the various posts have totally confused me as to what is normal for driving without a passenger in the seat...on or off?

If I sit in the passenger seat and turn on the key the console airbag light illuminates for a few seconds and then goes out. If I sit in the drivers seat it stays on. If I use my key to disable it then it stays off but then I would have to remember to turn it back on when carrying a passenger...this is not safe IMHO.

Since none of my other vehicles have had an airbag light illuminated as a normal driving situation I am concerned that there is something wrong. Was the BMW system designed to be illuminated when the seat is unoccupied? Anyone know the correct answer?

Thanks
The console light should only come on when you have deliberately de-actvated the passenge restraint system (which includes the passenger airbag) by turning your ignition key to the appropriate postion in the keyhole at the end of the dash (and removing the key after of course).
If you have set the "passenger airbag enabled" setting with your key then the console light should never be permanently on.
Seems like you may have a glitch in the electronics somewhere. Try and get an Indy to reset it but don't go to a dealer!

Thank You...I suspected it should go off after the self test but it's nice to get proper conformation. I'll have my Indy try a reset next time I'm in.

As an aside, there are many posts on several forums where people discuss this light being on as normal and they cover it up with tape..one person actually took it apart and black painted the inside of the lens...these other posts led to confusion as to what is normal and what is a malfunction. I greatly appreciate the clarification. :thumbsup:
 
As an update, I asked the dealer to check the airbag system a couple of days ago and I also asked them to look at the 10 years extended warranty on the occupancy mat. They read the codes and found nothing. Bottom line I must have both the air bag system light and the seat occupancy light on at the same time. So get this this fixed I need to trip an airbag code.
I seem to recall someone accidentally tripping the light when the had disconnected something under the passenger seat and then turned the key on before reconnecting. Can anyone confirm this and if so tell me what I need to disconnect in order to trip the light and a set an airbag problem code. Then I can go back to the dealer and qualify for the extended warranty repair ( I know, this seems dumb but so is the dealer's attitude towards qualifying for the repair)
 
Stromtech said:
Bottom line I must have both the air bag system light and the seat occupancy light on at the same time. So get this this fixed I need to trip an airbag code.
Sounds like a load of crop to me, but knowing something of inexplicable software logic, I suppose it's possible. I think your occupancy sensor mat is indeed defective, it thinks there is a light, non-adult on the seat though there is nothing there.

(Read entire post before actually following these instructions) You should be able to trigger an error by locating any convenient yellow connector. 1) Disconnect the battery, wait at least 30 min. (I've heard anything from 10 to 30 min, we are dealing with explosives here!) 2) Release the connector, reconnect the battery and start the car. This will trigger an error. 3) To restore whatever functionality existed, disconnect the battery again, and wait at least 30 min. again. 4) Reconnect the yellow connector, then reconnect the battery. Error should remain in memory. (I'm also not sure this sort of error will actually cause both airbag and occupancy lights to be on, but it will store a code)

However, some have reported clearing the code by disconnecting the battery, but it is extremely dangerous to attempt to reconnect an airbag connector with the battery connected. Perhaps just take the car in with the connector disconnected, tell them what you did, let them figure out what to do next. Then again, if they need a code to clear the error, they should be doing all this for you. You may want to consider an alternative shop before trying any of this.
 
Thank BCworkz...Only one BMW dealer on the Island so I must play by his rules. It's obvious the mat is defective but without 2 lights it's not going to get done.
The extended warranty document does say both lights must be on so he is following the BMW gospel. My job is to comply with the Gospel according the BMW and arrive at the dealership with both lights blazing. I'll be careful and follow your advice when I trigger the fault
 
So just as I am considering triggering an SRS light before the 10 year warranty extension...up pops the SRS light on it's own.

Took it in this morning and the occupancy mat was replaced under the 10 year extended warranty.
 
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