Air Bag Light

[ACS523i 0]

A while back my darling wife left the drivers window down overnight in the rain, and has also pivotted on her knees on the passengers seat - either or both of these could be a cause??

I am getting opinions on this at the moment - our e39 523i can't get it's warrant - our BMW guy here has diagnostics done on it and they came up as ;

1 - Internal fault within module.current

2 - Passenger seat occupancy sensor mat open circuit

3 - Driver seat belt tensioner circuit resistance low - driver seat belt tensioner possible fault or wiring harness.

He's talking some big $$$ to fix, do you reckon you can help? or suggest anything else?

Just want the bloody thing off so we can get a warrant. It's ridiculous that one of the safest cars in the world (with airbag or not) can get failed on this - hard to take when I saw an old Mitsi Mirage Geneva - circa 82' fly through it's warrant at the same testing place - the only airbag I could see in that was the old duck driving it

[camera doctor 25]

If it is the occupancy sensor in the passenger seat, you can buy a bypass plug on Ebay if you do not want to go to the expense of new sensor matt.

As long as you do not have kiddies in the front, will be OK. Just means passenger airbag will go off in accident.

You may still need the Airbag light reset at dealer or auto sparkies.

[*Glenn* 855]

No1 is a bit of a worry. What comes back after codes are cleared ?

No2 $500

No3 $250 to replace the wiring harness & another $200-250 for the receiver if needed. The wiring loom is a supercession

[*Glenn* 855]

If it is the occupancy sensor in the passenger seat, you can buy a bypass plug on Ebay if you do not want to go to the expense of new sensor matt.

As long as you do not have kiddies in the front, will be OK. Just means passenger airbag will go off in accident.

You may still need the Airbag light reset at dealer or auto sparkies.

Thats illegal and should not be promoted on this forum... total crap that can end up killing people.

[pureboiracer 0]

i dont know about bmws but with fords and mazdas if the light is on solid, not flashing a code, 9 times out of 10 its a dead module.

[nigel_1981 0]

Thats illegal and should not be promoted on this forum... total crap that can end up killing people.

How can this end up killing people exactly? My car has rear air bags, is it illegal for me to put children in my back seat?

[pureboiracer 0]

^because it is a non certified non approved modification to the airbag system in your car, the factory obviously put those sensors in the seat for a reason (and it wasnt to save money replacing unused airbags after a crash) the rear ones are probably designed to accomidate any possible baby seats that may be installed.

[sp8s 1]

Had the same thing caused by a d*ck kneeling on the passenger seat. Had one of those bypass things put in till I got a new mat for the passenger seat.

Now I have different seats (earlier NON airbag occupancy type sets) Mr WOF man (VINZ) said it was OK to use the bypass as the seats were not made for the occupancy mat. Go figure.

I will be reinstalling the original sport seats when they have been recovered then I HAVE to put the occupancy mat back in and wired up.

Man I get confused with all these rules and regulations, dont know how testers do it, understand all the rules that is.

In the days I did WOF's it was - lights work brakes work horn works yup she passed haha

[jochen 4]

i dont know about bmws but with fords and mazdas if the light is on solid, not flashing a code, 9 times out of 10 its a dead module.

On fighter planes, when the light is on, you're in big trouble.

In submarines, when the light flashes, you need to call the weapons center and get the cryptographer to decode the incoming message

On the moon lander module, it simply mean you were about to take a great step.

And on a BMW, it means... exactly what the BMW owners manual tells you.

Not the Ford manual , nor the Mazda manual, nor the fighter plane, submarine or moon lander manual.

The BMW manual is the one to read with BMWs.....

(walks away, wondering if he has made his point, and starts making bets as to who will groan and flame me...)

[Apex 693]

How can this end up killing people exactly? My car has rear air bags, is it illegal for me to put children in my back seat?

Back seat is fine, unless your kids are 6ft tall and 25kg.

Its because the front and side airbag will deploy even if there is no one on it or worse, a small child, the sensor is there to measure weight and activate the system, if it deploys with a small kid in the car it will knock there head off, worse, if it deploys with a shopping bag on the seat the side air bag will catapult whatever is in it at your head.

Just a thought and hypothetical situation.

I remember ours was all replaced under a BMW factory recall when it was a few years old, the loom, the pad the lot, guessing a few owners didn’t get the recall done.

Just rip all the air bags out and cage it.

[pureboiracer 0]

On fighter planes, when the light is on, you're in big trouble.

In submarines, when the light flashes, you need to call the weapons center and get the cryptographer to decode the incoming message

On the moon lander module, it simply mean you were about to take a great step.

And on a BMW, it means... exactly what the BMW owners manual tells you.

Not the Ford manual , nor the Mazda manual, nor the fighter plane, submarine or moon lander manual.

The BMW manual is the one to read with BMWs.....

(walks away, wondering if he has made his point, and starts making bets as to who will groan and flame me...)

from memory all vehicle manifacturers have to use universal codes and lights etc.. so in theory the code should be the same no matter what brand of car... i think its the same with abs and such but not 100% sure.

[nigel_1981 0]

There are many things that you could worry about, the E39 has an inherent fault that deploys the drivers air bag when you put the key in the ignition! (there was a recall). Bypassing the passenger occupancy sensor and then not putting young children in the seat is fine by me. I'd be more worried about a crash killing someone than an airbag deploying where no-one is sitting.

[pureboiracer 0]

as said above, its not the airbag deploying when no one is sat there that is the issue, its the issue of the computer thinking a fully grown man is in the seat and fully inflating the airbag when infact its just a little kid.

All im trying to say is bite the bullet and take it to bmw or somone similar and get it fixed properly, dont listen to these muppets with their bypass plugs because its not worth the risk. Its illeagle and dangerous because you wont know if it works until you go to use it. And its not something that u want to make patch up jobs with.

Edited September 29, 2010 by -Oli-

[*Glenn* 855]

The point is.... in NZ it is illegal to modify the system and to fool the system. It must be legaly repaired to comply to safety regulations... end of story... anything else you may do may cause the system to either work when it shouldn't or fail to work when it should. Your call if you want to f**k with your car and other peoples lives.

Just keep argueing

[nigel_1981 0]

There's no point arguing with you though is there?

[elmarco 56]

There's no point arguing with you though is there?

Not really because he is right.

[nigel_1981 0]

Not really because he is right.

Well that's your opinion and so well articulated.. If someone can explain to me how a (passenger occupancy sensor bypass) risks someones life then I'm all ears.

[pureboiracer 0]

Well that's your opinion and so well articulated.. If someone can explain to me how a (passenger occupancy sensor bypass) risks someones life then I'm all ears.

re read the last page, its said about 3 times....

what part of if the computer thinks a grown man is sitting in the seat because the bypass sensor is telling it its a heavy person and really its your 40kg eight year old then when the airbag fully inflates to take the impact of a 80kg man and snaps your kids neck back dont you understand?

and if its not your kid what about when you sell the car?

Edited September 30, 2010 by -Oli-

[nigel_1981 0]

re read the last page, its said about 3 times....

what part of if the computer thinks a grown man is sitting in the seat because the bypass sensor is telling it its a heavy person and really its your 40kg eight year old then when the airbag fully inflates to take the impact of a 80kg man and snaps your kids neck back dont you understand?

and if its not your kid what about when you sell the car?

Thank-you. It's now obvious to me you have no idea how the air bag works or why it does what it does, when it does it. FYI the passenger sensor DOES NOT determine "how much" to inflate the air bag based on the specific weight of the occupant.

In fact if computer thinks the sensor is faulty the system by (default) will always deploy the air bag. This is a choice BMW and it's lawyers have made in the interest of safety and/or court cases.

If someone is putting a small child in a car that SHOULD be in a kiddy seat but are not, then THEY are being NEGLIGENT. Otherwise if they're big/old enough not to be in a child seat you'd hope the airbag does inflate in the event of a massive side impact.

If, like myself you have watched side impact crash test videos of the E39 on youtube, and done the research you would have seen the location of where they deploy and how thin and shallow they are.

Again may I remind you I have rear air bags and they do not have passenger occupancy sensors, nor does BMW recommend you going to the dealer to have them deactivated if you carry children in the rear.

[Forrest 35]

Geez Oli how many dumb things can you post in one thread.

OP get it checked by a pro, opinions are like assholes around here.

Ninja edit: Well done Jochen

Edited September 30, 2010 by Brams

[Ben 0]

...and really its your 40kg eight year old...

Thats a fat kid lol

Probably woudnt need an airbag

Edited September 30, 2010 by Ben

[Apex 693]

It’s a 12 year old car, spending the money to fix it will be worth half the cars value no doubt, same problem occurred with my E39 plus quite a few more, added up the total and ended up selling it as parts as the fault repair costs outweighed the cars value.

POS.

Shame it’s so old otherwise BMW would have come to the party and subsidised part of the repair, they covered those parts for quite a few years under recall.

[nigel_1981 0]

I agree. This is why so many of these elegant, well made cars are now getting scraped for parts. It might be $330 for an inner splash guard or $500 to fix an airbag light that will probably come back in 12month. No thanks!

If anyone I knew asked me if a BMW was a good second hand car to buy I would say NO!!! If you actually have the money needed to pay service and retail, you’d be better off buying a brand new Mazda.

If you’re prepared to work on it yourself, get the parts you need from offshore or a wrecker, get on the forums, receive helpful advice from “open minded†strangers then do it. Otherwise keep walking.

[M3_Power 636]

I've not checked up on E39 airbag systems, but I do believe that 2 stage inflation was introduced sometime during that era or shortly afterwards.

I do also suspect that the E39 never received the now common and very sophisticated airbag systems that actually inflate at different rate of speed depending on occupancy weight (basically all the current generation BMW, hence why you can't actually just buy a sensor mat now if they crap themselves).

Having said that I am a believer that if you want to get it fixed, you should get it fixed properly.

There's a guy on trademe selling BMW seat occupancy sensors (they are for the E46 generation however) - perhaps ask him if he can get the E39 version - he has them for about $290. The occupancy sensors are quite easy to put in, once done it's just a matter of finding someone with a scan tool that can clear the code (or if you ever come up to Auckland I'd be more than happy to clear it for you on my GT1).

Good luck.

Edited September 30, 2010 by M3_Power

[elmarco 56]

Well that's your opinion and so well articulated.. If someone can explain to me how a (passenger occupancy sensor bypass) risks someones life then I'm all ears.

What part don't you understand? The concept of not cutting corners on safety related items? Or the legal, moral, and physical consequences of getting it wrong? The manufacturers don't put these systems into their cars just for the fun of it - if you know more about it than the engineer that designed it then take your case to the LTNZ. They are a core safety system and no matter how you bitch and moan about the cost of fixing it the law in NZ says don't f**k with them. Which I happen to agree with.

I for one would hunt down the former owner of my car if I found an airbag had been f**ked with and failed to inflate properly when I needed it most.