318iS Airbag light comes on and off when i have a passenger?

[richardrjs81]

Hello all hope you can help, i have looked on here but cant find a problem the same.
I have a 2003 318i sport touring, when its just me in the car all is fine but when i have a passenger the airbag light sometimes comes on but will go off and come on when it feels like it.

Any ideas, Many thanks
Rich

[harryinsaudi]

maybe a loose/shorting connector under the seat for either the occupancy sensor or the seat belt tensioning device.... You got anything trapped under the seat?

[jcharles07]

There are 3 items that could be your culprit, Occupancy sensor $23.00 on ebay, the seat belt buckle maybe $76.00 and the most terrible on is the mat sensor,not too easy to get it out, the dearler will charge more then $300.00 to replace it or look for some treads on how to replace it if all else fail...since it is intermittent you know is a short somewhere base on what you wrote, weight onthe pass seat might bite some wire and causing a short...

[FCPGroton]

I would think it was the occupant sensor first and for most. I had this issue on another one of my cars and that was the issue. I never fixed it because I never have passengers in that car.

[richardrjs81]

Thanks all, will take the seat out and have a look. If i unplug the seat to remove it and plug it back in will the light stay on?

Cheers
Rich

[marti5]

Disconnect the battery before you pull the seat out........if your radio needs a code make sure you have in case its required on reconnection.

[bw46508]

I had a similar problem in that my airbag light came on for no reason. Turned out it was my Passenger Seat Occupancy Sensor. This is a mat embedded in the seat and if it goes bad, then the airbag light will come on and all airbags are disabled (potentially). I got mine fixed by substituting this sensor with a bypass unit which simulates a passenger all the time. Check out the website:
Home

[bw46508]

Here is a link to a module sold on ebay

BMW E46 E39 E38 E36 Z3 Airbag Sensor Bypass Unit on eBay (end time 01-Oct-10 13:57:22 BST)