AIRBAG HELP - please

I'm currently swapping a UK MY00 steering wheel onto a UK MY95 and need some help on connecting the airbag - I was wondering if anyone could answer some fundemental questions:
1) How is an airbag triggered - i.e. simply application of high voltage or pulses?
2) What voltage is it?
3) Is there any solid-state circutary on the airbag itself?
4) Do the connections have polarity?
The old airbag and the Momo airbag have different connectors (still two wires). I'm going to splice the newer Momo airbag connectors onto the old socket but am unsure which wire is which. The old airbag has one wire with a black strip and another with a green, while the Momo bag has one wire with a blick strip and another plain wire.

Please, please can anyone help?

Cheers,

Andy

Hi.
I can't exactly help with your problem, but just a word of warning, stand well clear when you connect it up, these things can cause serious injury as well as save life. don't stand in front of it, and make sur it is well anchored to something cos if it goes of it woukld be like a small bomb, and you don't want that in your face.
Good luck!
Ron

Andy, I have read your subsequent post, if you want to e-mail with a contact point I'll speak to you tomorrow (Sunday), as you may have guessed I have already completed what you are trying to do,
regards

<BLOCKQUOTE><font size="1" face="Verdana, Arial">quote:<HR>Originally posted by andyp:
<B>I'm currently swapping a UK MY00 steering wheel onto a UK MY95 and need some help on connecting the airbag - I was wondering if anyone could answer some fundemental questions:
1) How is an airbag triggered - i.e. simply application of high voltage or pulses?
2) What voltage is it?
3) Is there any solid-state circutary on the airbag itself?
4) Do the connections have polarity?
The old airbag and the Momo airbag have different connectors (still two wires). I'm going to splice the newer Momo airbag connectors onto the old socket but am unsure which wire is which. The old airbag has one wire with a black strip and another with a green, while the Momo bag has one wire with a blick strip and another plain wire.

Please, please can anyone help?

Cheers,

Andy[/quote]

1. The airbag is activated by completion of the electrical circuit activated by the 4 G meters mounted around the chassis.
2. Like the rest of the vehicle it operates on 12V DC.
The SPS consists of 2 parts the bag itself, and the eletrically activated pirotechnic mounted in a chemical container (this is the Aluminium plate you can see under the plastic mounting frame. The third wire out of the bag of the multiplug goes to a potentiometer which has 12V running across it as long as the battery is connected, this voltage is cancelled out by an equal voltage as long as the multiplug is still connected. If you disconnect the multiplug whilst the battery is still connected the airbag warning light comes on (and stays on) until you do a master systems reset with some very technical gizmos from Subaru / I.M.
As you have already found the splines and shaft are the same on the early and late cars, this also applies to imports. If you examine the wheel itself the basic architecture and engineering is identical
Hope this helps!

[This message has been edited by JGRIFF (edited 16 September 2000).]

Thanks for the replies,

RON - thanks for the advice. I'd read a couple of threads before about the removing the airbag, and even though I'd disconected the battery for around half an hour I was still bloody nervous disconecting the thing. It was quite difficult fiddling with all the clips and wires with my kept well outside!

JGRIFF - as you say, the splines and peg-holes are identical (contrary to some info I've read about changing steering wheels in this BBS). Also, the elctrical connectos for the horn are identical, although the old wheel routes to the top and new one routes to the bottom so I had to swap leads. However, the yellow mutli-connector IS different. I'm going to splice the old connector onto the new airbag, but I'm afraid of connecting things up the wrong way round. Since it's only two wire I have a 50:50 chance.....do I feel lucky? ...well, not really - but I'll give it a go!
Only two leads go into the multi-plug and you mention a third - is this to ground?

Andy

Hi Andy,

with reference to the splines and taper being the same. It may have been me who gave you info to the contrary. I've never tried swapping wheelsm from a newer car to an older one, but the Momo boss I used to fit a non airbag wheel to it was of an incorrect taper and so the splines did not slide the full 8mm (from memory, total spline length is about 10mm on boss but only 8mm covers splines)with the momo boss they only covered the splines by about 3mm which I wasn't happy with. This was very scientifically measured with a marked toothpick!! Seriously though, the taper needed machining for the splines to fit and then the machining company ****ed that up anyway so I eventually sourced a boss from a breakers yard originally fitted to a legacy but it fitted perfectly first time,

regards,
Nito

Nito,

no worries about the info - I think sometimes we all get our wires crossed when talking about UK spec and Japanese Spec older models (i.e. airbag and non-aribag). As you say, a non-airbag (non-oem) Momo will have different splines and attachment than an oem Subaru Momo wheel - just because they both say Momo is no guarantee of compatible fittings. As you found out.

Cheers,

Andy

Hi Andy

Could I ask you where you got your steering wheel from and how much did it cost, as I am desperate to replace the horrible standard wheel on my MY96.

Would you also keep us posted as to your progress fitting the new wheel...perhaps with a step by step proceedure...if you have the time.

Also did you have any problems getting the old wheel off ie. did you need any special tools or puller.

[This message has been edited by stratman (edited 16 September 2000).]