BMW airbag light?

[onedirtygirly]

I thought whilst im asking for advise id also check and see if anybody knows what the best way of getting my airbag light off on my bmw 318 ti 1999 model its never had a bump and was fine untill 3 weeks ago its come on now and just wont seem to switch off I coud take it to the main dealer but i know it will be expensive and if prehaps one of you knows another way other than taking the bulb or taking it to the garage please could you let me know.
many thanks in advance
sab

[chassis 33]

I'd get it checked out by a dealer or indy, it could be a random light, or it could be indicating a fault in the wiring or with the unit itself, maybe something has come loose after clobbering one too many speed bumps or such like.

Much as I don't like post accident safety gadgets (I'd prefer not to have the accident in the first place), if it's fitted it may as well be working!

Regards
Iain

[GTRene]

maybe its not connected anymore...or they stole your airbag...those things happen too.
GTRene

[touching cloth]

Seat seasor failure is pretty common in BMW's, you could ask a dealer to reset the fault light (they did mine free) but it may come back on pretty quick (mine did). If it does come back on then my money would indeed be on the sensor failure which requires them to strip down the seat to get to and replace the sensor. Fairly pricey but can't for the life of me remember quite how much, think it might have been about £300-£400.

[jay123]

try looking under the seat and check if the connector is secure, it can get knocked while hoovering and that...

[catso]

touching cloth said:

Seat seasor failure is pretty common in BMW's

Not a BMW, but this happened in my car (Audi) when the seat was moved forwards it pulled a connector loose, was fixed under warranty but only required plugging back in and some slack making to prevent it happening again.

[CooperS]

touching cloth said:

Seat seasor failure is pretty common in BMW's

Tell me about it first thing that happend with the Z was the blinken warning light came up apparently the connector under the seat had worked loose?

Although 2 weeks later and the problem hasnt come back........ yet

[Dunk76]

If it's the seat - which as mentioned, it probably is, as they're easily knocked by feet/hoovering etc - then it's only £40 tops at Main dealer to reset the SRS system - most independants should be able to do it as well.

If the airbag light is on, then the entire SRS system is disabled... No airbags, no pretensioners.

[Burty124]

I had the same thing on a Z3 recently, probably just a fault code that needs clearing, about 2 mins on a diagnostic machine.

If there is a genuine fault the light will come back on, but you will then know what is wrong. On the Z3 it was the seat belt pretensioner, but once the fault was cleared it did not come back on.

The same car had the ABS light on, this was a fault with the right rear wheel sensor which, as we thought because the car was covered in crap, turned out to be dirt preventing it from reading correctly.

[silverback mike]

My wife caused a random airbag light illumination, she took her shoes off, and 'shoved' them under the seat, this dislodged the seat cable which in turn made the light go on.

I rummaged around and prodded some connections - it went out, and stayed out, so worth a rummage.

[grf500]

Not sure if this will help with the airbag light but it certainly helps with resetting all the other lights....

Simply turn the ignition on (not the engine) and leave for 15-20 mins.

It worked for my brake sensor lights when I changed the pads and discs.

[off_again]

grf500 said:

Not sure if this will help with the airbag light but it certainly helps with resetting all the other lights....

Simply turn the ignition on (not the engine) and leave for 15-20 mins.

It worked for my brake sensor lights when I changed the pads and discs.

For BMW's though, the airbag light remains on regardless if the fault has been cleared or not. It can only be reset by a specific tool. Obviously all BMW dealers have these, some indies do too (and you can now buy them for £100 each). Its a bit of con though - no way of clearing if unless you get it reset.....

[blackspider]

It will either be the n/s or the o/s seat belt pre tensioner loom-the connector under the seat is the cause.The fault can be erased but will come back shortly after the fix is a modified loom which is cut into the existing loom under the seat(floor to pre tensioner).
The other is the n/s seat occupacy mat(under seat base swob)they tend to go open curcuit(break in the mat)or there is a control module for the mat which sits under the seat base(its just slightly larger than a match box in black)9/10 its one of those.

The air bag light cant be reset by disconecting the battery or turning the ignition it can only be reset via a BMW diagnostic tester or one of the after market tools(snap on,mac tools)

The air bag system will still work to its fullest potetial even with a fault in the system-the part with the fault will still be attempted to fire in an accident by the control unit.If the mat has failed then the control unit will presume there is a passanger sat in the seat and fire the n/s seat belt and airbag if it has one.

[off_again]

blackspider said:

The air bag system will still work to its fullest potetial even with a fault in the system-the part with the fault will still be attempted to fire in an accident by the control unit.If the mat has failed then the control unit will presume there is a passanger sat in the seat and fire the n/s seat belt and airbag if it has one.

Is that right?

There has been quite a bit of debate on various BMW message boards about this - some say it will work while others say its disabled completely. From what I understand from what a BMW technician said, it is my understanding that it will "fire" what it can, but if a sensor (say the front crash sensor) isnt working then you cannot expect it to work if you smack something. But equally there have been some good comments saying that it will not work....

[blackspider]

off_again said:

blackspider said:

The air bag system will still work to its fullest potetial even with a fault in the system-the part with the fault will still be attempted to fire in an accident by the control unit.If the mat has failed then the control unit will presume there is a passanger sat in the seat and fire the n/s seat belt and airbag if it has one.

Is that right?

There has been quite a bit of debate on various BMW message boards about this - some say it will work while others say its disabled completely. From what I understand from what a BMW technician said, it is my understanding that it will "fire" what it can, but if a sensor (say the front crash sensor) isnt working then you cannot expect it to work if you smack something. But equally there have been some good comments saying that it will not work....

The MRS III/IV will try to trigger any airbag or pretensioner that may have an intermittent or permenant fault.
The warning light is to let you know there is a fault in the system and to have it looked at asap,in the mean time the system will still work as well as it can-unless the control unit is dead or the componant has a perminant failure
There are 3 crash sensors in the system-2 side impact(under the carpet) and 1 acceleration sensor (in the control unit).If one fails it will use the other 2 as reference.
If the occupancy mat fails then the control unit has to assume there is someone sat there and fire the bags during an impact.