Crawls Backward (When Alarmed)

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Airbag Removal, Steering Upper Bearing Bushing Replacement on SAAB c900, Pt. 1

The last few times that I drove my SAAB convertible (aka SAAB #2, really my fourth...), I noticed a lot of up-and-down play in the steering wheel.  By a lot of play, I mean like 1/2 an inch (about 12mm) or more.  It was a bit disconcerting.

So I did some research on the interwebs and figured out it might likely be a bushing that sits in the back of the steering shaft bearing and rides between the bearing and the shaft.  Made sense to me, so I procured the parts.

In the meantime, I drove SAAB #1, my 3-door 900S.  This is where it's a good idea to have more than one.

Anyway, let's get on with the bushing replacement.

We need to remove the airbag, so the first order of business is to disconnect the battery.  I disconnected the negative lead.

There is a capacitor that stores energy to fire the airbag. so by disconnecting the battery, and then waiting about 20 minutes, the cap will discharge and the airbag will not go "poof" in our face when we undo it.

Center the steering wheel before you take the bag off - the alignment is important for the infamous 'clock spring' horn contact ring which we'll see soon enough.

There are 2 T-30 fasteners behind the steering wheel which hold the airbag to the wheel.  Undo them.

Then gently remove the airbag from the steering wheel.

That's it.

Wow.

Now you know why stealing airbags out of late-model cars is popular.  It's simple to take them out.  But please DON'T steal airbags!  Thieves are the scum of the earth.  Don't be one.

And fortunately for us, there is not much of a market for c900 airbags.  Unlikely that yours (or mine) will get stolen.

Before you can get the airbag the whole way off the car, you'll need to undo the connector on the back of the airbag.  It just slips off.

This is the backside (hee hee) of the airbag.

And here's the label.  Notice it was NOT made by Takata.  Duh.

With the airbag out, you can now access the wiring and connectors for the airbag and the horn buttons.

I like the tidy way the wiring is routed within the wheel through those molded-in clips.

The big nut in the center holds the steering wheel on.  Note also the alignment pin just below the nut.  The pin is molded onto the top half of the contact ring.

You'll need a large wrench or breaker bar to get the nut off.

I'm pretty sure the nut is a 22mm.  I couldn't find my larger sockets, so I used a 7/8 inch socket, which worked fine.


 The airbag connector is already undone, and we just need to undo the horn connector.  That's the black connector the arrow is pointing to.

Then, carefully push the connectors back through the access slot in the steering wheel - that's where the blue arrow is.

Pulling the steering wheel out will help get those connectors through the hole.  Just wiggle on the wheel and it will slide off.

Here I have the wheel most of the way off, and you can see the airbag and horn wiring from the back.  At this stage, it can be fished through the hole in the wheel.

Notice the black round piece behind the wires.  This is the horn contact ring.  Proceed with caution at this point.  The ring is in two halves and you don't want them to be separated if you can avoid it!

You can guess what happened to mine.

So now we have the steering wheel off, and we need to remove the horn contact ring.  This piece is also known as a 'clock spring.'  It's two halves.  The top half is free to turn with the steering wheel.

The bottom half is attached to a steel plate.

I had read on the interwebs about "don't let the clock spring come apart" but without pictures or a good description, I wasn't clear about it.

You, dear reader, are now educated about this, you can proceed with caution.

The best approach is to tape the halves together.  This picture was actually taken when I put the contact back in, so I had taped it together.  I advise doing it when taking it out.

There are 2 screws that hold the contact to the plate.  Remove them.

The two wires for the horn are attached to the front, or top, part of the horn contact.  There are also 2 wires on the back side of the switch.  First we need to get the contact off, then undo the 2 contacts on the back.
 
Once the 2 screws holding the contact ring are removed, you can slide the ring up the steering shaft.

If you look at the picture on the left, you'll see that the 2 halves of mine began to come apart!  WHAAAAAA!  Note the contact ribbon itself - the white object that looks like a reel of tape - inside the connector.

At this point, I realized what was happening, and I taped the thing together, but not before a wind or two of the ribbon came out.  Fortunately, the world DID NOT end!

The catch here is that you cannot fully remove the contact ring until you've undone the two connectors on the back.

Undo the two screws holding the turn signal switch bottom bracket to the top of the bracket.  If your car has never been apart (mine had not), you'll still have the factory cable tie on the wiring - you can cut it off.  (I put a new tie on when it went back together).

Sorry that some of these pictures are a bit blurry - it was overcast and I had some camera shake, what with a tool in one hand and the camera in the other.  But you'll be able to see what's happening.



Now you can easily get access to the connectors and separate them.

Then the contact ring can be slid off the steering shaft.

I didn't mention the function of the contact ring.  It ensures that there will be electrical contact to the horn buttons and the airbag while the steering wheel is being turned.  It's basically a big reel of ribbon connector that loosens or tightens as the wheel is turned. 

Now you'll have access to the third screw on the mounting plate and that can be removed (it was already removed in the picture above).

That's enough excitement for one post, I think.  We're actually pretty far along.

 
 
 
 

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