airbag indicator
 

I have the airbag indicator showing on my dash. My mechanic says that
it's the connector that is bad. He has reset it 3 times already and usually it'll come back on when the rear pass. door opens and then shuts. Can the airbag wiring connector plug be the culprit?


:bmw:

Could be the wiring loom going to the door.

i also have the airbag light.disconnected the battery twice and checked the fuse for it.no luck

This might be a long shot, but have you considered the font passenger seat occupancy sensor? I have just recently got rid of the air bag light, in my car. There is a pressure mat in the passenger seat that detects if there is a passenger or not. From what i can understand, this determines the amount of air bags that are deployed in the event of an accident. When the pressure mat dies, it will throw the light up on the dash. This light is indicating that in the event of an accident, ALL of the air bags will deploy no matter what. The reason i bring this up is that maybe when you open and close the rear door it is disrupting the sensor in some way. My air bag light was on and off for months, then it just stayed on all the time. There is cheap and easy fix for this, which I stumbled across on YOU TUBE. I will try and give a more detailed explanation of how to fix the problem. This should really only take about 30mins to complete. You will require the following items:-

* 2 x 100 Ohm resistors
* 1 x 1N4001 diode (I used a 1N4004, which is close enough.)
* Heat Shrink tubing
* 1 x soldering Iron
* 1 x pair of wire cutters

Once you have all these items together, you can create what some people may call 'The seat occupancy sensor bypass'.

First of all, you will need to locate the sensor under the passenger seat. The easiest way to do this is to adjust the seat all the way forward and raise it as high as it will go.

Now for the fun bit... Lie on the floor of the rear passenger side and look up underneath the rear of the front seat. Right near your head there will be a small rectangular box approx. 70mm long x 40mm wide attached to the underside of the seat This is the sensor.

You will note there are wires going in and wires coming out. The ONLY wires you need to worry about are the BLUE and WHITE wires.

You will also note there is a plug with BLUE and WHITE wires attached to it. Disconnect this plug and have a pair of wire cutters handy. Hold the plug in your hand and cut the blue and white wires, leaving approx. 30mm of play between the back of the plug and where you are cutting, as you will need this to solder the bypass to later on.

Once you have done all this, you can peel yourself of the floor of the car and head into the workshop! (With plug and wire cutters in hand)

You will need to solder 1 x end of one of the 100 Ohm resistors to one end of the Diode. Then repeat with the 1 x remaining resistor on the other end of the Diode. There is a silver band at one end of the Diode this end will be connected to the BLUE wire in the future.

You can place heat shrink over the whole thing at this point, but be sure to mark on the heat shrink, which end the silver band of the diode was on. this is IMPORTANT.

Carefully bend this contraption into a 'U' shape, with the diode at the bottom of the 'U'.

Solder the free end of the resistor attached to the silver banded side of the diode to the BLUE wire hanging off the plug. Now solder the end of the other resistor to the WHITE wire.

Now you can now heat up the heat shrink and voila! Head back to the car, lie on your back and plug it back together! The sensor mat will now be disconnected from the sensor and hopefully this will rid the light from your dash!

I recommend that you have a quick look at this video on YOU TUBE How to bypass BMW Passenger Seat Occupancy Mat sensor for passenger Airbag - YouTube , to give you a better understanding of what i have just described.

Hope this makes sense and fixes your problem.

Cheers,

Ben

Great post & thanks for the info!

Is there anyway to test if the airbag light is on because of the seat occupancy sensor, before you actually bypass it?

Dealer/Indy should be to easily figure out what part of the system is bad. I would recommend against using the resistor trick. If you ever sell the car, you'll find yourself liable if you don't return it to stock. My X came with 2 resistor tricks from some dickwad repair shop. If I would have gotten t-boned, the wife wouldn't have some airbags. BMW dealership accidentally came across one of them when they were looking at something else....and then decided to check the whole car.

Yes, as recklessspyder said, you will most likely need to go to an indy to determine if this really is the problem. However,the only thing that this 'resistor trick' will do is ensure that ALL the airbags deploy, in lieu of only deploying the air bags that the car thinks is necessary at the time. You can spend thousands of dollars replacing the sensor mat that is stiched into the seat or you can spend 10 dollars and have a fully functioning system and no light on the dash!

Hmmm, its a catch 22. If they all deploy when say only the steering wheel one would have been required, and you are not going through insurance for whatever reason, the cost of replacement (and replacement panels where necessary) for every airbag in the car could be very high. If you want to fix it properly, the cost of a new seat pad is very high also.

I had an M3 which hit a kirb very VERY hard. No damage to the car other than a crack in the bumper and the door air bag went off. I sorted the damage myself very cheap and with a replacement air bag from a breaker. Now if every airbag went off the cost of repairing it would have been silly.

rock & hard place :dunno:

That's a very good point! I guess i just wanted to get rid of the pesky little light on the dash quick, cheap and easy... Your best bet is to go and have somebody check it out to determine what the issue actually is, as my resistor fix may not cure your problem at all!

So if the air bag light is on and its a fault of the passenger seat mat/sensor, are all air bags disabled in an accident or just the passenger side only?

I will search for the threads on replacing the mat. Sometimes the light goes out when I hit the cushion of the passenger seat. Thanks.