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Discussion Starter #1 (Edited)
To remove the steering wheel on a model-year 1990 (or later) Classic 900, you have to deactivate the airbag.

The Bentley book is full of warnings about the dangers of this safety device (nice oxymoron there), but doesn't say how to deactivate it; this dark secret, apparently, must not be divulged to the Great Unwashed.

While searching the web recently, I came across a page written about 10 years ago for emergency/rescue personnel--who need to know how to deactivate undeployed airbags at accident sites. In this document were, of course, instructions for the Classic 900's airbag system.

Disclaimer: I consulted with other Moderators before posting this information. The consensus was that it should be posted, with the understanding that anyone using this information does so at their own risk.

Method 1: Disconnect the negative battery cable. Next, wait 20 minutes--this allows power stored in the SRS control module to dissipate. Now you can pull apart the orange 2-wire connector under the dash (lower dash panel must be removed for access). The steering wheel can now be removed.

Method 2: Remove the lower dash panel. Pull apart the orange 2-wire connector. This supposedly disarms the airbag instantly, but Bentley claims the connector's pins short together when the connector is pulled apart. See page 371-133 (and wiring diagrams on next 2 pages). Because I don't know what Bentley means here, I advise following Method 1. Alternatively, cut the 2 wires, one at a time so the cutter's blade doesn't short them, leaving the connector in one piece.Resolder the wires later.

BTW: These two problematic wires feed the airbag through slip rings on the steering column. The rings, and their contacts, wear over time and often cause the cursed "false-alarm" blinking of the SRS warning light in the dash.
 

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Is it possible to remove this plastic conector from under the wheel? One day I have tried to remove my airbag steering wheel and fit a nice Nardi, and I didn't know what to do with that conctor... It looks like it's a horn sealed with plastic. With that conector on steering column it's not possible to fit a nardi/momo 900 hub, it just can't fit there...
BTW maybe someone could post some pictures of hub aligment, becouse after I failed to mount this wheel I am not sure if may hub is a 900 or 9000...:confused:
 

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Uhh...disconnect the battery. I removed the steering wheel in my car because I was replacing the dash. Just Remove the - battery terminal cable. Worked for me...no air bag explosion here.
 

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Discussion Starter #4
tomikk said:
Is it possible to remove this plastic conector from under the wheel? ... It looks like it's a horn sealed with plastic.
If it has 4 wires, it is the slip-ring assembly. Remove the 2 screws, and lift it off the steering shaft.
 

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ProfZ said:
BTW: These two problematic wires feed the airbag through slip rings on the steering column. The rings, and their contacts, wear over time and often cause the cursed "false-alarm" blinking of the SRS warning light in the dash.
ProfZ,

Are the slip rings you talk about above on this website at the very bottom of the page? The part numbers are:

8972374
8954281

http://www.thesaabsite.com/900old/c900airbagcomponents.htm#AIRBAGS+%26+RELATED

A few related questions:

1) How do I tell if the slip rings are worn?
2) How do I know if I do not have to replace the entire Horn contact ring ($132.00!!!) to fix my blinking SRS light problem.

Regards,
-vbadoni91
 

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Generally the clockspring is worn if the SRS light is on and everything else is fine. But even if you replace it, SRS will still blink until reset by the SRS computer tool thingy at the dealer.

Saab's procedure is to wait 20 minutes after disconnecting the battery. There is a capacitor that stores energy to fire the bag and run the system if there is a severe impact within say 5 minutes of battery power loss (eg you hit something that knocks out the batt, then get hit really hard by something else), so Saab says wait 20 just in case.
 

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900t said:
Generally the clockspring is worn if the SRS light is on and everything else is fine. But even if you replace it, SRS will still blink until reset by the SRS computer tool thingy at the dealer.
Hello 900t,

1) Referring to the two part numbers in my post, which of the two components is the "clock spring" you mention above in?
2) Do I need to change the entire Horn contact ring (the one that costs $132)?

-vbadoni91
 

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Yeppers the super expensive one. You should be able to adapt something from another car. It's just a thing that allows the steering wheel to turn. You could even just splice in a length of wire long enough to allow you to turn the wheel to lock :cheesy: Not as elegant a solution nor as long-lasting but...

The airbag was made by Siemens IIRC and is pretty popular on cars of that vintage, Porsche had the same system with a slightly different steering wheel.

To be honest I wouldn't even bother with it. Typically what happens is at some point in the operation of the car, the SRS loses contact in the contact ring, triggering the code, but the ring is still "good", though over a long time may develop a "dead spot" somewhere along the wheel's rotation. Probably if you had the ECU reset by a dealer, the light would stay off for a fairly long period of time. I'd still expect the bag to function when needed, and if the bag doesn't fire, it's not like it is a potentially fatal failure (a 900 is safe enough without it).
 

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900t said:
Yeppers the super expensive one. You should be able to adapt something from another car. It's just a thing that allows the steering wheel to turn. You could even just splice in a length of wire long enough to allow you to turn the wheel to lock :cheesy: Not as elegant a solution nor as long-lasting but...

The airbag was made by Siemens IIRC and is pretty popular on cars of that vintage, Porsche had the same system with a slightly different steering wheel.

To be honest I wouldn't even bother with it. Typically what happens is at some point in the operation of the car, the SRS loses contact in the contact ring, triggering the code, but the ring is still "good", though over a long time may develop a "dead spot" somewhere along the wheel's rotation. Probably if you had the ECU reset by a dealer, the light would stay off for a fairly long period of time. I'd still expect the bag to function when needed, and if the bag doesn't fire, it's not like it is a potentially fatal failure (a 900 is safe enough without it).
If I get it from another car (a junker probably), chances are that the clock spring is worn on that one too. So it is the expensive piece... That is a bummer... But wait a minute... Here is a post where "Smackrazor" says that it was just a corroded contact which cost him only $12 to fix...

http://www.saabcentral.com/forums/showthread.php?t=622&highlight=airbag+light


-vbadoni91
 

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Exactly... what is happening is the resistance is too high somewhere. Open it up, you might just be able to take some sandpaper to it and boom it's fixed :lol: It will still flash, you need it reset.
 

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900t said:
Exactly... what is happening is the resistance is too high somewhere. Open it up, you might just be able to take some sandpaper to it and boom it's fixed :lol: It will still flash, you need it reset.
OK I will try that one of these weekends.
 

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ProfZ said:
Method 1: Disconnect the negative battery cable. Next, wait 20 minutes--this allows power stored in the SRS control module to dissipate. Now you can pull apart the orange 2-wire connector under the dash (lower dash panel must be removed for access). The steering wheel can now be removed.

Method 2: Remove the lower dash panel. Pull apart the orange 2-wire connector. This supposedly disarms the airbag instantly, but Bentley claims the connector's pins short together when the connector is pulled apart. See page 371-133 (and wiring diagrams on next 2 pages). Because I don't know what Bentley means here, I advise following Method 1. Alternatively, cut the 2 wires, one at a time so the cutter's blade doesn't short them, leaving the connector in one piece.Resolder the wires later.
I went to SAAB SRS school in 1988. This is what they said:
Method 1 is the recommended procedure.
When the plug on the back of the airbag is disconnected, the contacts in the airbag, not the plastic connector, short together. This is to prevent the possibility of static electricity setting off the explosive.
It is forbidden to cut and splice any part of the SRS wiring, it changes the resistance.
All the connectors are gold plated, don't corrode, and shouldn't be sanded.
 

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Jim Mesthene said:
All the connectors are gold plated, don't corrode, and shouldn't be sanded.
Jim,

Is there an outside chance that the slip rings and the connectors might be causing this problem?

All,

I am taking my car to a Saab independent shop. BTW, I was told be by the service advisor that a momentary spark or short while disconnecting the battery can also lead to the SRS light coming on. Can anyone corroborate the SRS light coming on in their car with them fiddling with the electricals prior?

In any case the fail code will be pulled tommorrow. So we shall see. I am hoping that is it and a reset of the light would do the trick...

-vbadoni91
 

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vbadoni91 said:
Jim,

Is there an outside chance that the slip rings and the connectors might be causing this problem?


I was told be by the service advisor that a momentary spark or short while disconnecting the battery can also lead to the SRS light coming on.
There are no slip rings, the steering wheel contact is a ribbon of plastic, with conductors embedded, that coils and uncoils as you turn the wheel. The coil fails often, the connectors don't.

In my experience, it is impossible to set a code without a malfunction having existed.


I should have mentioned in my previous post, that whenever you disconnect the airbag, the first plug that should be removed is the one on the airbag itself (this contradicts the fire department, you should never disconnect any other plug in the system while the airbag is connected). The other connectors don't short themselves and so there's a moment of risk while the airbag is plugged in but the system is not intact.
 

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Jim Mesthene said:
There are no slip rings, the steering wheel contact is a ribbon of plastic, with conductors embedded, that coils and uncoils as you turn the wheel. The coil fails often, the connectors don't.
Thanks Jim. Thsi plastic ribbon I would assume are a part of the "horn contact ring" I metion below ($132)?

Jim Mesthene said:
In my experience, it is impossible to set a code without a malfunction having existed.
Today I will find out what that code actually is...


Jim Mesthene said:
I should have mentioned in my previous post, that whenever you disconnect the airbag, the first plug that should be removed is the one on the airbag itself (this contradicts the fire department, you should never disconnect any other plug in the system while the airbag is connected). The other connectors don't short themselves and so there's a moment of risk while the airbag is plugged in but the system is not intact.
Do you mean that the orange 2-wire connector that ProfZ mentioned in the original post is not the one to be pulled apart? If not what is the identification of the connector that is to be pulled? Is there a particular color?

-vbadoni91
 

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vbadoni91 said:
Thanks Jim. Thsi plastic ribbon I would assume are a part of the "horn contact ring" I metion below ($132)?


Do you mean that the orange 2-wire connector that ProfZ mentioned in the original post is not the one to be pulled apart? If not what is the identification of the connector that is to be pulled? Is there a particular color?
SAAB used to call it a "coil, contact". I don't know what the latest term is; $132 sounds like the right part.

Correct. Do not unplug that first.
SAAB wants you to disconnect the battery, wait 20 minutes, then unscrew the 2 security Torx screws that hold the airbag to the wheel, unplug the airbag, then proceed.
That's what they told us in school in 1988.


Disclaimer:
Flat-rate mechanics don't have 20 minutes to wait. After having been trained in how the system works, we came up with shortcuts.
Because of the danger involved (the airbag is filled with explosive, not air), I will not share any of the shortcuts.
It was impressed on us at school that the airbag is an explosive (expensive to ship, markings required), and they have killed people. We used to have to detonate them before shipping back warranty returns (so they did not have to be shipped as explosives); anyone who has seen one go off will understand their power. We were supposed to open the windows a little so they wouldn't get blown out. Any airbag equipped car has its windshield glued in with sealer to keep it in place during airbag deployment.
Just because you've had no problems yet, do not assume the airbag can't kill you if you subject it to improper handling. The white powder residue after deployment is toxic.
 

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Jim Mesthene said:
SAAB used to call it a "coil, contact". I don't know what the latest term is; $132 sounds like the right part.

Correct. Do not unplug that first.
SAAB wants you to disconnect the battery, wait 20 minutes, then unscrew the 2 security Torx screws that hold the airbag to the wheel, unplug the airbag, then proceed.
That's what they told us in school in 1988.


Disclaimer:
Flat-rate mechanics don't have 20 minutes to wait. After having been trained in how the system works, we came up with shortcuts.
Because of the danger involved (the airbag is filled with explosive, not air), I will not share any of the shortcuts.
It was impressed on us at school that the airbag is an explosive (expensive to ship, markings required), and they have killed people. We used to have to detonate them before shipping back warranty returns (so they did not have to be shipped as explosives); anyone who has seen one go off will understand their power. We were supposed to open the windows a little so they wouldn't get blown out. Any airbag equipped car has its windshield glued in with sealer to keep it in place during airbag deployment.
Just because you've had no problems yet, do not assume the airbag can't kill you if you subject it to improper handling. The white powder residue after deployment is toxic.
Man! Thanks for the sobering post. I really mean it THANK YOU!

-vbadoni91
 
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