So many airbag lights. - BMW Forum

cjscopp · 07-07-2008, 01:53 PM

New to this forum coming over from Benzworld having owned and repaired MBZ's for decades. My 19 year old daughter wants an E36 but in looking at many used ones I am seeing almost every one with the airbag light on. What gives? Is this a normal weak spot on the E36 or am I just lucky? From the schematics I see seat pad sensors and seat belt switches which MBZ does not use so this is a little new to me. Anyone care to comment if this is an area of concern. I searched for this issue but found only older posts with not much info.

Thanks
Alan

johnnyBgood · 07-07-2008, 02:24 PM

Quote:

Originally Posted by cjscopp

New to this forum coming over from Benzworld having owned and repaired MBZ's for decades. My 19 year old daughter wants an E36 but in looking at many used ones I am seeing almost every one with the airbag light on. What gives? Is this a normal weak spot on the E36 or am I just lucky? From the schematics I see seat pad sensors and seat belt switches which MBZ does not use so this is a little new to me. Anyone care to comment if this is an area of concern. I searched for this issue but found only older posts with not much info.

Thanks
Alan

I know when you remove a steering wheel or a front seat for any reason without 1st disconnecting the battery the light will come on & stay on, until reset.......
johnny,

darkhorse737 · 07-07-2008, 03:04 PM

Hey there... Sac'to as well :-)

to the werkz.

i wouldn't say weak spot, really...

On BMW's they use a pad sensor for the airbag/s that are susceptible to moisture when you shampoo the carpet or get the floor wet; drive in the rain; or ... some drunk passenger spilling a drink on the floor ... (for one reason or another).

johnny bayonne is also right in his post. In the 1st place, it is bad mech practice to toy around with steering wheel ans airbags without first disconnecting battery and letting it sit at least 15mins before commencing work ;-)

Not a major issue and definitely correctible. We're actually in luck bcz we have the recycle yards in Rancho Cordova where replacements can be had for cheap ;-)

I'd say seeing airbag lights on cars you have seen is purely coincidental. And if it's ON and up for sale, it's probably because the seller doesn't want to assume the load for repairs(almost always $1000+ at the dealers... for whatever reason).

You've worked on MBZ before... then u know it could just be a loose wire ;-)

David Mc · 07-08-2008, 03:02 AM

Front passenger seat occupancy sensors and seat belt latch sockets are common faults and both easily fixed. Airbag light activations give you strong bargaining power in purchasing a used BMW. I got $3000 off for an airbag light activation that turned out to be a bad front passenger seat sensor. I built a little circuit which fools the airbag module into thinking the front seat is always occupied for less than $1 and reset the light which has stayed off ever since (the circuit is described in this link 4shared.com - document sharing - download Seat Occupancy Sensor ByPass.pdf ). The only downside is that both airbags will deploy in the event of a crash. A replacement sensor was about $250 and I will instal it myself when I get the motivation.

cjscopp · 07-08-2008, 09:32 AM

Thanks for the tips. I have also found lots of ABS lights on. Seems like lots of wheel sensors go bad and it motivates the owner to pawn off the problem by selling the car. The thing is though that they all want full KBB private party retail even with the problems, go figure. Going to see a 1994 325i this afternoon that has no airbag light on but does have the ABS light on. Guy's asking $6200 for it which is WAY out of the ballpark even for a dealer but I'm goint to look at it anyway and see how far down he might go.

darkhorse737 · 07-08-2008, 03:09 PM

try the Sacramento Craigslist as well... lotsa bargains there(sometimes...) ;-)

dwagz · 07-09-2008, 11:50 PM

It's probably the front seatbelt switch (located in the seatbelt lock housing). The airbag will Not deploy (Is Not Functioning) when that light on the dash is on. In my case, the dash light turns off turns off after about 20 or 30 seconds as the system has corrected itself. (I've already replaced 2 (two) front-passenger seatbelt switches in my '96 328ic under warranty).

cjscopp · 08-05-2008, 07:18 PM

Well folks we got one! After looking at too many pieces of junk I found a real gem. 1995 325i with the sport option. This one qualifies for the KBB catagory of excellent. Picked it up this afternoon and my daughter is very happy. The only thing to do is the drivers seat leather. It has the sport seats with the extending front. Anyone know an aftermarket supplier of leather covers?

darkhorse737 · 08-06-2008, 09:07 PM

try eBay

or if you do the Roseville auctions at Denio's there's a fellow there that does custom seat covers for cheap.

cjscopp · 09-02-2008, 09:52 AM

August was quite a month for our family. First we got the 1995 325i sedan for our daughter. Great little car with the sport option. Daughter decided she wanted sheepskins, so instead of doing the leather were just gonna cover it up and deal with it later. Secondly, the Mrs was rear-ended by a hit and run driver and her 1991 300SE Mercedes was totaled. After the insurance paid off we picked up a 2002 525i with the sport option. Buying 2 new BMW's in one month makes it a big month for us. Here is a pic of the 325 and our new 525 is my avitar.

Mr T Man · 04-30-2010, 05:36 AM

Like I've mentioned in my other post:

I had the same problem. The light is really annoying. The guy at the garage said the airbags will not deploy if it is not fixed which is really worrying when you are trying to concentrate on driving! Followed the link from one of the previous posts BMW Airbag Warning Light Passenger Occupancy Sensor spoke to the Bimtronics Team and got the Simulator.

This is a PROFESSIONALLY made device. I WOULD NOT RECOMMEND MAKING ANYTHING YOURSELF unless you are a qualified professional technician!! It's just not worth the risk!!!

Ask yourself....Would you make your own wheels? No, you would just go out and buy some that were made professionally, otherwise you would be risking your life and your passenger's life!!

BE SMART AND SAFE

David Mc · 04-30-2010, 07:55 AM

Do you cook your own food so that you don't risk food poisoning? If you want professionalism, bite the bullet and replace the defective component. As far as paying a "professional" an inflated price for a circuit (which was designed by a pro) that can be built for $1, I think that is just rip off economics. The other option is deactivation of the defective sensor using dealer-level software, which can also be used to reactivate the sensor when it has been replaced.

Torque · 04-30-2010, 03:38 PM

I'm pretty sure if there's any fault with the system, aside from a faulty crash sensor, the airbags will deploy ... so if you have a bad pass. occupancy sensor, chances are the airbag will deploy whether or not there is someone there; there isn't a chance in hell it will not go off because of a bad occupancy sensor.

David Mc · 04-30-2010, 03:56 PM

Correct - all this scare mongering about the airbags not deploying at all in the event that the warning lamp is on is rubbish. At worst, if the passenger seat occupancy sensor is faulty, passenger side airbags will not deploy as the car will think that the passenger seat is unoccupied and will not arm the firing circuit. This will have no effect on the normal operation of the drivers' airbag.