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Discussion Starter #1
Mate has a Z3M Coupe with door bags. One of the things that bugged him was the trim covering the door airbag on the passenger side. He removed it one day and the airbag has deployed at some point and the unit left in with the material of the airbag cut away.
So could you reset the dash airbag light after this so it doesn't stay on ? Currently the airbag comes on when the key is inserted and goes out as normal when you start the car. Would that be correct ?
Thanks
 

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Sounds right, lights comes on at startup and goes out if all is ok, stays on if there is a fault etc, sounds like someone has cleared the error code.

More worrying though why was the bag deployed ? Is the car damaged
 

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If the bag has deployed then the light should be on, which would make me want to get to the bottom of why the light goes out????????

The airbag fault codes need reading first of all, :thumbsup maybe the light has been wired up on a timer, :shifty:

What year is the Z3M?
 

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Discussion Starter #5
Thanks all. The car is a 98 model. It has some paint on the passenger side and I can see that a dent has been pulled out of the passenger side rear wing, but the door is either orginal or a replacement done perfectly...apart from the airbag of course...
I'll get him to check your suggestion of a timer and look at getting any fault codes read.
Thanks
 

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Thanks all. The car is a 98 model. It has some paint on the passenger side and I can see that a dent has been pulled out of the passenger side rear wing, but the door is either orginal or a replacement done perfectly...apart from the airbag of course...
I'll get him to check your suggestion of a timer and look at getting any fault codes read.
Thanks
Thats not right mate, you'll probably find the clocks have been out (paint off the screws) and a wire going from the ABS light to the Airbag light so it turns it out.

If thats the case your other airbags won't go off in a bump unless a resistor has been placed across the blown airbag..

HTH :thumbsup
 

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The light is working correctly for a system with no errors ie light comes on whilst system goes through self diagnostics, turns off if everything OK, stays on if there is a problem.

So far as I know (not sure about side airbags which were an option even on the ///M's) the system should fail its diagnostics (ie the light stays on) until a deployed airbag has been replaced. Even if the system is reset the diagnostics will just fail again on the next ignition.

Its a common fault on the seatbelt pretensioners which are part of the SRS system diagnostics for them to cause the light to stay on due to the connectors under the seat being "knocked" and BMW changed the harness for an upgraded one.

Some people leave the light on without realising that if any part of the SRS system fails the diagnostics and the light stays on the entire system is turned off (ie the steering wheel /passenger airbags which will not deploy if needed), even worse some people remove the bulb meaning when the sell the car the new owner is non the wiser until/if they realise the light never comes on during the diagnostics (but most don't realise this!).

If is possible to "fool" the diagnostics into thinking that the faulty part of the circuit is OK as it works on expected resistance readings. You can for example buy kits to bypass the seatbelt pretensioner check on eBay and if you fit a non airbag steering wheel (or fit a single stage airbag to a later >04/99 dueal stage system car) you can bridge the circuit with a 3 ohm resistor.

It maybe that the side airbags are not part of the SRS diagnostic check but I find this unlikely meaning that the circuit has probably been bypassed in some way rather than pay for a replacement airbag :jaw-dropping (especially as the diagnostics seem to be working correctly by the light function)

At the end of the day the side airbags were an options and most Z3's don't have them at all so not as big an issue as bypassing the steering wheel or seatbelt pretensioner circuits.

nb if you did decide to source and fit a replacement airbag you would need to find the bypass and remove it ;-)
 
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