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Old 02-14-2013, 03:35 PM
rebel.ranter rebel.ranter is offline
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Location: Cork, Ireland
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Mein Auto: M6, 630i, 320iC
Has anyone been kneeling on your passenger seat recently?
The most likely cause of an airbag light coming on is a failure in the seat occupancy sensor. There is a webbing built in to the passenger seat that detects occupancy when the webbing is stretched. If someone were to kneel on it (or heavy/rough use) the webbing can break leading to the system getting erroneous readings.
Sometimes the connector for this sensor can work loose if the seat has been recently moved backwards & forwards. Another potential cause of the airbag light illuminating is a faulty seat belt tensioner or the wiring to the seat belt tensioner.
Really you need to get the fault codes read to determine the exact cause as there are many more reasons that can cause the airbag light to illuminate. Even a failing car battery can cause errors in the airbag system. There is also a pyro charge on the positive battery terminal which deploys like an airbag in the event of a crash, the pyro charge explodes internally & breaks the positive terminal circuit in the process, its a safety measure. These units, like airbags report resistance values back to the airbag control module, if the control module doesn't get the expected values then the airbag light goes on.
Get the codes read.

Last edited by rebel.ranter; 02-14-2013 at 03:40 PM.
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