Cant reset Airbag warning light!

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phb10186
Joined: Sun 16 Sep, 2007 07:18
Posts: 383

  Z3 roadster 2.8
Location: London and Bournemouth

Cant reset Airbag warning light!

Post by phb10186 »

I had the airbag light come on a few months ago, and I was told that, when it failed to reset last time, that it was the occupancy sensor in the passenger seat...

I fitted one of these boxes from ebay that had a resistor inside it, and when I took the car to the garage today, it still failed to turn off with the OBD reset tool... It goes off, then comes back on in about 5-10 seconds each time it is reset.

What else could it be, this is a real pain???
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1998 2.8 M52TU, pre-facelift, hard top, montreal blue, tan interior, 91K
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c_w
Joined: Thu 19 Aug, 2004 16:50
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  M roadster S50

Post by c_w »

Best bet is to go to an independent with a proper diagnostic tool and thye can pin point the cause without having to guess.
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Justin Time
Joined: Thu 22 Jun, 2006 20:34
Posts: 2183

  Z3 roadster 2.0
Location: Kent

Post by Justin Time »

There are many components in the airbag system, only a link up to a diag machine will give you definate answers.
BMW Z3 2.0L Velvet Blue Individual Edition
phb10186
Joined: Sun 16 Sep, 2007 07:18
Posts: 383

  Z3 roadster 2.8
Location: London and Bournemouth

Post by phb10186 »

Occupancy sensor fault!!!! I have bought and fitted the bypass resistor, I'll have to have another look at the wiring then... what else can I do?
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1998 2.8 M52TU, pre-facelift, hard top, montreal blue, tan interior, 91K
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Jonttt
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Joined: Sun 28 Dec, 2008 16:32
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  M roadster S54
Location: Liverpool

Post by Jonttt »

Maybe the bypass unit is faulty you got from eBay?
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phb10186
Joined: Sun 16 Sep, 2007 07:18
Posts: 383

  Z3 roadster 2.8
Location: London and Bournemouth

Post by phb10186 »

jonttt wrote:Maybe the bypass unit is faulty you got from eBay?
I have just taken the seat out again, so I can have a look, the only problem is that I don;t think I can drive the car.....

Can anyone confirm that I can drive the car with the passenger seat out...

There are 3 connectors to the seat:

1. Power for the seat motors
2. Passenger occupancy sensor
3. Seatbelt Pre-tensioner

If I remove the entire seat, is it safe to plug just the parts of (2) back in to the car, and leave (1) and (3) disconnected.

Basically I have the box that fools the system that the passenger occupancy sensor is connected, so I can plig all that in, so the car thinks the seat is in place, it's just the question of leaving the power to the seats off, as well as the seatbelt pre-tensioner disconnected.... can anyone verify if it is safe to do so? This will allow me to fiddle with the passenger occupancy sensor in order to reset the blooming light, without having to put the seat in/ out each time.

thanks, Ben
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1998 2.8 M52TU, pre-facelift, hard top, montreal blue, tan interior, 91K
AntMan
Joined: Sun 16 Dec, 2007 17:28
Posts: 448

  Z3 roadster 2.8
Location: Derby

Post by AntMan »

Your pretensioner will give you an air bag light if not connected the electric seats won't matter though.You could possible unbolt the pretentioner from the seat so you can also leave that in the car as well so you can confirm fix without the seat in.
It shouldn't cause any issues it's just looking for the sensor connections only thing i'm not sure on is if the pretensioner needs an earth taken through the seat frame i don't think it does but it might again at worst i imagine it to show the light but at least the code would be pretensioner and tell you weather you have fixed your occ seat sensor problem??
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phb10186
Joined: Sun 16 Sep, 2007 07:18
Posts: 383

  Z3 roadster 2.8
Location: London and Bournemouth

Post by phb10186 »

OK, thanks for the head's-up, simpler to replace seat TBH, v. annoying to have to do this each time though!
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1998 2.8 M52TU, pre-facelift, hard top, montreal blue, tan interior, 91K
Just Dave
Joined: Sun 15 Mar, 2009 13:16
Posts: 6

  Z3 roadster 1.9

Airbag warning light

Post by Just Dave »

Hi there, I wonder if you or anyone reading can help me out, I have an airbag warning light on, I fitted leather seats from a 2003 model (mine is a 1999) I assume the airbag seat pads are irrelevant as I'm sure there there were none on my original seats, I have however swapped the seat belt retainers / pre tension units. I have removed the seats before with no issues however this time I drove the car and the airbag warning light wont go out, any ideas !!
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Robert T
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Joined: Mon 12 Jun, 2006 10:35
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  Z3 roadster 1.9
Location: Cheshire

Post by Robert T »

Did you disconnect the battery while you worked on the seats? If not, that is very likely the cause of the problem, as even a momentary break in contact in any of the connectors will bring the light on.

Cheers R.
Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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Just Dave
Joined: Sun 15 Mar, 2009 13:16
Posts: 6

  Z3 roadster 1.9

Post by Just Dave »

Robert T wrote:Did you disconnect the battery while you worked on the seats? If not, that is very likely the cause of the problem, as even a momentary break in contact in any of the connectors will bring the light on.

Cheers R.
No, I went straight ahead and disconnected the plugs from the seats. It gets worse, I've been looking for obvious signs of a loose connection etc and I've found the clutch master cylinder that connects to the clutch pedal leaking, ant idea what one of those costs ! However I still love the car and as you can probably tell I've only just bought the car and I'm new to the forum, any advice is greatly appreciated and thank you very much for your time.
Cheers
Dave
Just Dave
Joined: Sun 15 Mar, 2009 13:16
Posts: 6

  Z3 roadster 1.9

Post by Just Dave »

No, I went straight ahead and disconnected the plugs from the seats. It gets worse, I've been looking for obvious signs of a loose connection etc and I've found the clutch master cylinder that connects to the clutch pedal leaking, any idea what one of those costs ! However I still love the car and as you can probably tell I've only just bought the car and I'm new to the forum, any advice is greatly appreciated and thank you very much for your time.
Cheers
Dave
Just Dave
Joined: Sun 15 Mar, 2009 13:16
Posts: 6

  Z3 roadster 1.9

Post by Just Dave »

Sorry guy's I don't know whether to post a reply or a quote !! I'll get there shortly !
Dave
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