Seat adjustment & airbag light.

UK forum for general and technical discussion about the Z3 roadster
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TerryO
Joined: Fri 23 Sep, 2011 11:37
Posts: 32

  Z3 roadster 1.9
Location: Yeovil

Seat adjustment & airbag light.

Post by TerryO »

Hi, I'm new to the forum as I only bought my 98 1.9 Roadster a couple of months ago, having PX'd my MK2 MR2. It's not our main car and is really intended for weekend trips etc :lol: . My only gripe is that I have a few niggly problems with the electrics. I recently removed the dash pod because the right hand side (tacho & temp) were not illuminated. Whilst out I also had to replace a couple of the smaller warning bulbs. I now find I have the airbag light on continuously. I made sure I disconnected the battery prior removing the pod and kept the key out of the ignition the whole time. So I guess the original airbag light must have been one that had already blown! A fellow Z owner has tried to reset it with his SIR VIII tool, but the light comes back on after the car is driven a few yards. I was going to check the plug connectors under the seats, but I have since discovered that the passenger seat adjuster is not working in either of the up or down directions. Could the fuse to the passenger seat have blown and would this cause the airbag light to remain on? Assuming the seat occupancy sensor is powered by the same line. The fuse box cover lists the fuse numbers on a sticker, but the actual fuse box positions don't appear to be numbered. Cheers, Terry.
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aceman
Joined: Sun 01 Jun, 2008 11:16
Posts: 1479

  M roadster S50
Location: Wakefield

Re: Seat adjustment & airbag light.

Post by aceman »

Hi Terry,

Welcome to the forum you have come to the right place but one thing you need to do is post some pics up of your car we all love looking at one anothers pride and joy.

To the problem in hand I suspect you have two problems rather than both being related. Firstly the airbag light is usually a result of the wiring to the seatbelt pretensioners getting chafed by the seat mechanism resulting in a shorted wire or even a wire totally disconnecting. BMW did produce a wiring mod which basically extended the wire so it could be re-routed out of the way but with some simple wiring additions this can be done yourself. As the light is immediatly coming back on as soon as you reset it I suspect one of the pre-tensioners has become totally disconnected so delve in under the seat and check the wiring.

The other problem is quite common also with the seat mechnism sometimes getting stuck which if you persist in trying to move the seat can result in the fuse blowing. The airbag circuitry certainly will not share the same fuse in the name of safety so this is coincidental. Maybe removing the seat to inspect the seat mechanism is in order as it will give you easier access to the pre-tensioners as well making the job a little easier.

I am sure somebody else will be along who has experienced this and offer some more advice but the main thing you must remember is to post some pictures up before you attempt to repair your zed. :D
Aceman

Arctic Silver '98 Z3M

Previously;
Bright RED '99 Z3 2.8

Rocking seats ? You need seat bushes click HERE
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GazHyde
Joined: Fri 26 Feb, 2010 21:27
Posts: 1347

  Z3 roadster 2.0
Location: Royal Wootton Bassett

Post by GazHyde »

Hi Terry,

You say the previous owner reset the light, but did his gizmo read the fault(s) produced with the lights?

I bought a relatively cheap airbag reset tool which also gives a list of fault codes so you know which bit is faulty...

Got mine from http://www.bavariandominator.co.uk/page ... ent_294575

If you ever pass Swindon way you can pop in for a free go with mine.

Gary.
Kornknarr
Joined: Fri 05 Aug, 2011 19:07
Posts: 169

  M roadster S50
Location: Uppsala, Sweden
Contact:

Post by Kornknarr »

My passenger chair did not move when I bought mine. The reason was that it was stuck in one of the extremes. I took out the chair and unbolted one end of the mechanism. You can find a photo here (if you ignore the Swedish and scroll down a bit) with a red arrow pointing to the bolt i undid. I then loosened the mechanism, greased it, and then my lady could enjoy the ride.

The airbag light was also on. I couldn't get it off myself. The dealer said he couldn't either but when he returned it it was off and have stayed that way...? it's obviously one of the most common faults there is on these cars.
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pingu
Joined: Fri 30 Apr, 2004 16:01
Posts: 3412

  M roadster S50

Post by pingu »

My prediction is...

The airbag lamp was blown when you got the car (possibly deliberately). Did the airbag light come on and then go off when you first switched on the engine? It should.

I think the little yellow connector under the seat has become disconnected. This will disable the airbag system and illuminate the dashboard light.


Solution

Read the airbag fault code(s) using an SRS Airbag Rest Tool. Cure the fault. Clear the error.

I don't know how you will get behind the seat if the motor is kapput. You need to be able to move the seat to get it out :shock: .
Pingu
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Ian_C
Joined: Sun 10 Dec, 2006 20:10
Posts: 2415

  Z3 roadster 2.8
Location: Lytham St Annes

Post by Ian_C »

pingu wrote:I don't know how you will get behind the seat if the motor is kapput. You need to be able to move the seat to get it out :shock: .
I think it's only the up/down not working pingu - you can get the seat out if fwd/back is working.
Current...1998 ///M Coupe
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Previously...1997 Z3 2.8
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TerryO
Joined: Fri 23 Sep, 2011 11:37
Posts: 32

  Z3 roadster 1.9
Location: Yeovil

No seat adjustment & airbag light on.

Post by TerryO »

Thank you for the replies. I'll try checking the fuse first as there's no sign of life in the passenger seat adjuster at all, so it won't move vertically or back & forth. I wouldn't think both motors would jam up at the same time? As you say, without being able to slide the seat back & forth it's impossible to gain access to the seat mounting bolts. If I manage to get the seat out I can then check the connectors & hopefully fix the airbag light.
I'll post some pics of the Z soon. It's a basic example of the 1.9 pre-facelift in Arctic silver. It has a few miles on the clock & several pevious owners, but a full service history. I've just recently replaced both front wishbones because of split ball joint gaiters etc. I've also fitted EL dials. I find the car more entertaining than the old MR2. Today the wife & I went for a spin through Cheddar Gorge with the top down, excellent!
swamper
Joined: Thu 13 May, 2010 17:14
Posts: 1866

  M roadster S50
Location: Mossley

Post by swamper »

Terry before you go to any lengths in regard to the seat motors try popping off the seat switch cover and try moving micro switch by hand......the covers or the switch become worn and don't connect with each other....hence no movement..
the badness makes me do it...!

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GazHyde
Joined: Fri 26 Feb, 2010 21:27
Posts: 1347

  Z3 roadster 2.0
Location: Royal Wootton Bassett

Post by GazHyde »

Terry,

There is a trick to moving a seat forward without power to the motors. I know there is a thread on here with a better explanation, but here goes...

The motor for back/forwards is under the front of the seat in the middle. There are 2 drive spindles going to the runner on each side of the seat.

You can pull the bars out of the motor in the middle (with a bit of force by pulling at one end of the bar!). You will find a round metal bar, with square spring ends on (see picture below). One of the square ends can be clamped in to the chuck of a cordless drill, and you then wind the seat out manually. Be careful with how much power you use, as it can destroy the square ends quite quickly (I luckily had a spare!).

You need to move each side about an inch or so at a time. You will also need to figure out which way to wind each side, remembering to reverse the direction on the drill on each side. It will be clockwise on one side, and counter-clockwise on the other side.

Hopefully that makes some sense, but I followed that procedure to remove my passenger seat which was dead!

Regards, Gary

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GazHyde
Joined: Fri 26 Feb, 2010 21:27
Posts: 1347

  Z3 roadster 2.0
Location: Royal Wootton Bassett

Post by GazHyde »

Just found this diagram which should help.

You can see the motor (3), and one of the spindles (4) at the left hand side of the diagram. It doesn't show the other spindle on the exploded bit, but you can see it in situ on the main seat base.

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pingu
Joined: Fri 30 Apr, 2004 16:01
Posts: 3412

  M roadster S50

Post by pingu »

Page 172 or 174 of this is the wiring diagram for the passenger seat.

The common parts seem to be the feed from Fuse 5 (30A), the switch and the earth. I suspect the feed or the switch.
Pingu
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