Mine has been on for some time, and it's now an MOT fail issue.

It came on after my independent mechanic changed the rack pinion valve, which involved taking the steering wheel off, as well as part of the column, so I understand.

He has checked the codes, and it appears to be the bag or connection, not the under-seat cabling.

I've yet to dismantle and examine. I'm aware of the battery disconnection and capacitor discharge precautions. What are the likely weak spots? I've read somewhere that it's often the ribbon cable. Is this unobtainable?

Experience and observations welcomed!

r

'97 2.5

Hi Rg

I have the wheel and steering column from a "T" reg estate that I am in the process of scrapping.
Plus all the airbag and seat bag wiring and sensors.
The light was working correctly prior to the cars demise.
All put to one side ready to take record photos as I pulled it to bits.

John

Hi Rob,

I'm not sure why the steering wheel had to be dismantled to do the pinion valve. The bottom of the column can easily be disconnected without disturbing the steering wheel or Airbag.

In any case, there are three connectors on the air bag. After disconnecting the battery and waiting a few minutes the steering whel cover can be removed to expose the connectors. I suppose it should be a matter of disconnecting and reconnecting to see if that cures the problem. What I'm not sure of is whether the light will go off even if you solve the problem. I don't have enough experiance of air bags to know if the light goes out when the fault clears or if you need to plug in the Lexia to clear it. You can but try I suppose.

The removal of the steering wheel cover to gain access to the air bag is shown in the following self help file.
http://club-xm.com/forum/index.php?showtopic=341

Cheers

noz

John,

Thanks for your kind and prompt response - I have sent you a private mail.

Noz.,

Thanks, as ever, for your generous diligence in putting together the self-help files, and running the site - you are an XM legend! Is your blood type LHM?

The work was done a couple of years ago now, and I took my chap's word for the access issue - I'm amazed that they could get in from the top anyway!

The steering wheel had come off, as it was put on slightly off-centre by one of their younger staff. Plus, I could hear something rattling in it after the light had come on.

This may just be a connection issue, but I need to be pre-armed with a parts source should it not be.

Thanks, both!

Rob

Hi Noz & RG

Have replied to the PM.
I think it is the next loom down the column that is the problem.
In the later XM's it changed from hard wired cables to plastic film strip connectors.
It is then very easy to crimp and crack the copper film track to cause a failure.
Can often be an intermittent fault.
They are also fairly easy to test and find the crack.
Repair needs a minimum temperature soldering iron and a single strand of thin wire.
Or two spots of conductive glue and the wire strand.

John

In my experience it is usually the rotary switch behind the steering wheel. Interesting to read you can use glue to fix this but I wouldn't know how to find which string would be faulty? I always replaced the whole unit. Ihave done 3 sofar, never could visually see anything wrong with them. It isn't difficult to replace at all.

The latest...

I got the cables and ribbon cassette off this lunchtime, and there appears to be some disruption where the ribbon cable leaves the outer case of the cassette (on the "engine bay" side, not the "airbag" side). It's a point where the ribbon cable rubber sheath has a 90 degree angle to leave the cassette. The copper cores are visible.

The cassette fell apart when io took it off, so it's obviously been disturbed at some point, and not put back in place properly.

I've done a continuity test with a meter for the pair (with the orange connector) that feed the airbag (with the airbag removed!!) and, not surprisingly, got absolutely nothing.

It looks too hard to repair here, as it would involve splitting the sheath which would not go back together again well, but is essential for strain relief.

For identification the "engine side" of the rear of the cassette has a paper stick-on label which reads:-

61620004
9627442580

Cast into the plastic is:-

>PA6.6+M0S2<

The airbag side has the following cast into the plastic:-

Valeo 6162 Made in France

I wonder if this is common with other French vehicles of the period, and if it is now deleted from PSA's stores?


Rob

Just FYI, mine differs from the one in Noz's picture. I didn't take it apart...

Airbag Harness

Wow, completely different. I take it the reel acts like a pull start on a lawnmower with teh white ribbon cable recoiling into the black plastic reel when the steering wheel is turned left or right? Apart from coming to bits in your hand is there any evidence of breakage?

In the one I photographed there seemed to be space for the explosive and the bag. There seems to be no depth to yours. Where are the explosive and bag located?

curiouser and curiouser,

cheers
noz

The control (firing) ECU is now integrated with the seat belt one in the central console.

John

Noz.,

This is not the only case of puzzlement over these devices. "Becky" from the XM-L group had an igniter like yours, and we couldn't work out why mine was nothing like it.

Various bits of the loom are out of view, but I can post another image.

I can't recall right now how it came off, and the relation of the central coggerd spool to the outer smaller cog, but will compare when I put the replacement one on, which will be kindly supplied by XMexclusive (Thanks!).

The indie's junior has clearly butchered the old one, which is why it came apart in my hands, hence the broken ribbon cable.

r

Hi RG

Note that the cassette has a pictorial warning about needing straight wheel positions on assembly.
The big question is about any difference between set up position of a factory cassette verses the random set up of a secondhand one.
I think the car had wheels almost straight to put it into my work unit and hopefully I have not molested the cassette.
Perhaps that the cassette popped after reassembly because of set up error.

John

John,

Thanks for the advice, as ever. Yes, I'd seen the warning but hadn't quite fathomed it. It will all be reassembled with a large degree of caution.

The whole reassembly of this area was way below what I normally receive from my independent, as recent inspection has revealed.. One of the lads was dismissed not long after my work, and I suspect it was the one who did this little bit of damage.

r

Folks,

John kindly supplied a replacement harness, and the light has gone out. Phew.

Many thanks, John! Prompt and friendly service is much appreciated!

r