Airbag Light - What have you tried?

I haven't seen these mats in the flesh, but would not be surprised if you couldn't see an actual break. I would suggest a 2007 mat as these are different if reading above is correct.

I also doubt BMW would test for you.
 
Daffy said:
Should I buy a 2004 mat for 2007 seats of a 2007 mat?
?

Does this mean you have a retrofitted 2007 seats into a 2004 Z4 or vice versa? In that case, the electronics (for sensor mat) should be all the same manufacturing year i.e. for a 2004 car, a 2004 control module and a 2004 sensor mat (from your old seat or from BMW). For a 2007 car you would need a 2007 sensor mat and no control module in the seat.

DMike
 
That's right - 2004 car with 2007 M-Seats in which the mat is apparently damaged.

You think i should use an 04 mat in 07 seats rather than keeping them standard?
 
You will have to use the at appropriate part to the year of your car, well without reprogramming the car. I have just fitted 2006 msport seats, and am having the issue you are.

At the moment i have taken the box and cable from my old seats, and used an ebay bypass box to get round retro fitting the 2004 mat, as i dont want to be ripping the seats apart really. But hopefully i will retro fit the airbag button so i can just turn off the passenger airbag anyway, therefor eliminating the need for the seat sensor anyway, well sort of :D

I still have to get the light reset, so fingers crossed it works, but it should do!
 
chris said:
You will have to use the at appropriate part to the year of your car, well without reprogramming the car. I have just fitted 2006 msport seats, and am having the issue you are.

At the moment i have taken the box and cable from my old seats, and used an ebay bypass box to get round retro fitting the 2004 mat, as i dont want to be ripping the seats apart really. But hopefully i will retro fit the airbag button so i can just turn off the passenger airbag anyway, therefor eliminating the need for the seat sensor anyway, well sort of :D

I still have to get the light reset, so fingers crossed it works, but it should do!

Im thinking about getting some other seats - so what ebay bypass box have you bought - links?
How many connectors under there? I took the drivers seat out when doing the new trim install and there only seems to be one yellow connector under there - are there more under the pass seat?
 
Same connector, but the passenger seat has more connector blocks in it, as there is power, seat belt tensioners and seat occupancy sensor on the passenger side. All only fit in one way, and very easy to get out etc.

The bypass box was from ebay ages ago when i had my e46, and the sensor failed (common problem). So all ive done is wired up the new seat with the old wiring and stuck this box on the end, instead of the seat mat plug. Its only two wires and i had the old plug on it.

It says on the ebay links they do e46/z4's/e39's etc etc, so it should work. But since ive put the other wires in, its triggered the light to come on. I went off on the e46 without having to reset it, but im sure the newer ones always come on and stay on, instead of resetting themselves.
 
Daffy said:
That's right - 2004 car with 2007 M-Seats in which the mat is apparently damaged.

You think i should use an 04 mat in 07 seats rather than keeping them standard?

The 2007 sensor mat is probably not damaged, but incompatible with the 2004 car's electronics. I think you need a new 2004 sensor mat and a 2004 seat module (from your old seat or dealers). I also had the airbag light with sensor mat fault code when I replaced my 2005 seats with 2006-7 M-seats. My post facelift seats mat had a transparent box with electronics, whereas pre facelift mats are simple and have a separate module underneath the seat base. The sensor mat connects to the module and the module to the seat's connector. PM me if you need a picture of the 2005 seat module.

The sensor mat pins in the yellow connector are the same, but the signaling is different: If i recall right, volt metering my 2005 seat showed a simple pressure-correlating current, whereas the post facelift seat had a more complex oscillating signal. BMW WDS showed that some functionality was indeed moved from the seat to the car's airbag modules. I ordered a 2005 mat and left the post facelift mat in place (disconnected).
 
yg54sg said:
Perhaps someone could post a pic of which modules do what under the seat? From what I can see I have at least 3 boxes. :cry:

This is the module from my 2005 standard seat, which connects to the yellow connector and the sensor mat. The same module worked fine with a 2005 M-sport seat's sensor mat.

DMike
2005%20sensor%20mat%20loom.jpg
 
One thing, if I use the seat bypass box so the car thinks there is someone there. Will the alarm for the seatbelt go off? As that will annoy me ! Or does it use a different sensor?
 
chris said:
One thing, if I use the seat bypass box so the car thinks there is someone there. Will the alarm for the seatbelt go off? As that will annoy me ! Or does it use a different sensor?
Depends. If the bypass cheats the car to believe someone is seated, the seatbelt alarm will go off and the airbag will deploy in an accident. Or, if the bypass tells the systems that the seat is unoccupied, neither the seatbelt alarm nor the airbag will work. Personally I wouldn't bypass any of the safety systems or use non-OEM parts. Insurers may have an opinion too...

DMike
 
It bypasses the system in thinking someone is sat there. So the seat belt alarm will go off then!

How hard is getting the mats out? Right ball ache i bet!

As i am getting the airbag switch, or iirc you can have the passenger airbag turned off permanently anyway, so may just do that. As ive got to have it turned off.
 
chris said:
It bypasses the system in thinking someone is sat there. So the seat belt alarm will go off then!

How hard is getting the mats out? Right ball ache i bet!
Remove seat, remove some trim plus backrest. You will find most instructions in BMW TIS. Open some metal rings in rear of the seat base, change mat and close the leather again. For this last step try meticulously document (photograph) everything you open. Once the rear of the seat is open, take your time to study the interiors of the seat; I'd recommend placing thew seat on a table and have plenty of light available. Allow a complete day, if you haven't done it before. M-seats have a few transverse metal bars (like ribs) sewed in the leather, which are fastened to the seat pan from below. Cable ties and a metallic wire hook (made from a metallic hanger) came handy when refastening these. I managed to close everything neatly and the seat came out perfect, but I wouldn't recommend beer or equivalent beverages during the surgery. I think an upholstery company would be happy to do the job.

DMike
 
Took the car for MOT yesterday asked them to look further into airbag light, they ran some tests and the problem was the BST which cuts power in a crash, turned out to be a loose battery terminal! Argh if only i'd checked! £100 later and its all fine :driving:
 
Ahhhhhhhhhh! got in my Zed Friday morning and the bloody airbag warning light has come on, quickly reading through this am I right in guess ing the likely cause is the occupancy in the passenger seat?

I'll check all the connections I can tomorrow, but is there any way of narrowing this down without a trip to the stealer.
 
RichardG said:
Ahhhhhhhhhh! got in my Zed Friday morning and the bloody airbag warning light has come on, quickly reading through this am I right in guess ing the likely cause is the occupancy in the passenger seat?

I'll check all the connections I can tomorrow, but is there any way of narrowing this down without a trip to the stealer.

It could be the pasenger seat mat or any one of dozens of aibags, connectors, looms, etc. In any event it's a trip the dealer or specilaist to turn it off as it won't reset itself, so oyu may as well just book it in to diagnose, if simple fix and have it cleared.

Went through smilar with mine when I did the seats and work on the doors and soon after had the aibag light on. Turned out to be a totally unrelated problem with the loom to the passenger door airbag.
 
Just booked into Teesside Autotech on Thursday afternoon for a diagnosic, be interesting to see what it brings up, especially after reading some of the horror stories on here, then consider the next step over the next few month's while I'm sunning (errrr I mean working very hard) myself in Brazil.
 
Mine came on after a long road trip and the dealer had to replace the sensor module (covered under warantee). When I rang from France they said that it could mean the airbags wouldn't deploy properly!! Still drove back and had it sorted on my return rather than wasting a day in a French dealership...
 
Had a diagonostic and the fault reset carried out by Teeside Autotech on Thursday, bit pricey at £47.00 inc VAt for an Indy. But beggers can't be chooser's, one disadvantage of living in the sticks is the lack of choice.

Anywhooo, only fault that showed up was for a Tyre Pressure failure to reset, he cleared that and as far far as the Airbag warning the system actually told him there were too few errors, which he'd never seen before, so far the light has stayed off but the truth in the pudding will be in December when I get home to see if it stays off and start driving my Zed again.
 
Okay Chaps: the verdict.

1* IF you've replaced your standard pre-facelift seats with post facelift M-seats, you WILL need a new Occupancy Sensor mat. :thumbsdown:

2* If you have an SRS light on and BMW have said it's the mat. This can be done at home (with a little time and cursing) it took me about 4 hours. :cry:

You'll need Torx bits, Needlenose pliers, Snips and Patience. :headbang:

You'll need A Prefacelift M-sport Mat and about 20 zip ties.

Cost (complete £155) just the mat £105. Cost at Scothall BMW Leeds £375 :thumbsdown: . Saving £270ish! :thumbsup:

My sensor is off and staying off.

Perfectly functional.....just in time for sale.
 
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