Recently I was experiencing electrical problems with my Saab 9-3 Aeros steering wheel controls.

The symptoms started with the volume up control not working. A few weeks later the horn operation became intermittent and then quickly stopped working altogether. This was followed by occasional airbag warnings which would come and go sporadically.

After some internet research, I determined that the most likely cause was breakdown of the rotary coupler (aka clockspring) behind the steering wheel.

These cars use a canbus system and the switches have differing resistances so that they can be connected to the electronics with fewer wires. Breakdown of the clockspring prevents the electronics from correctly identifying which switches are being pressed.

Now, the great big blue bottle in the ointment is that the clockspring is part of the CIM assembly. The CIM (column integrated module) is the brain for the locking and ignition system and is only supplied by Saab dealers as a complete assembly, brand new at over £400 +vat +fitting + programming. Ouch.

Secondhand CIMs can be had from a variety of sources usually for about £180 to £250 depending upon feature. Mine having both traction and ESP was the expensive one.

After more research, I found Brooke Saab near Chester. Andy Brooke buys faulty CIMs and strips them for parts and offers a CIM rebuild service. All other Saab specialists only want to sell you a used CIM complete.

Some faults can be fixed (steering sensors and some board faults) but the rotary coupler is impossible to fix so the only option is a secondhand one (Delphi will not supply them on their own - nice!).

I could have sent my CIM to Brooke for rebuild, but this would have meant having my car off the road for several days. As an Engineer and experienced car DIYer I decided to do the rebuild myself. Andy Brooke was really helpful with advice and agreed to sell me a clockspring for £60.

I watched several videos on Youtube to learn how to remove the steering wheel and CIM. After removal it was a simple matter using a Tx screwdriver to take the CIM apart. It is necessary to ensure that the clockspring is not wound hard against either end stop when off the vehicle or it will fail again in the future. Everything clips together and is easy enough to rebuild with a little care. You need to transfer over the original steering angle sensor too (clipped to the side of the clockspring).

As Haynes like to say, replacement is the reverse of removal. The whole job took less than 2 hours.

unfortunately though, it is not possible to rebuild the CIM without disturbing the steering angle sensors, so these need to be reset.

They can be reset by a specialist or dealer equipped with Tech 2 diagnostics or an independent with Bosch diagnostics.

I found Bignall Saab in Birmingham and went to them. They have Tech 2 and the reset took 5 minutes. Bignall were also helpful with advice and I had a great chat with them about possible future works (I want a stainless Maptun exhaust with 100 cell cat).

(there is a Saab independent nearer to me in Rugby, but I found him to be unhelpful and somewhat abrupt)

NOTE: Vauxhall dealers cannot reset the steering angle sensors and neither can independents with Snap On diagnostics. Both these systems think they are connected to a Vauxhall car and ask for a passcode to carry out the reset. On Saabs no passcode is required, Tech 2 and Bosch systems recognise they are connected to a Saab and so don't ask for a code. So if you're going to use an independent ask if they have Bosch or Tech 2.

Other issues with the CIM are well documented, but include other gremlins with column switch operation and problems with key coding and thus starting.

I'd thoroughly recommend speaking to Andy Brooke about a CIM rebuild and then finding a local Bosch equiped independent to carry out the work (or to use for the steering reset after you've rebuilt it yourself).

If you are an independent with Bosch dignostics, bone up on these repairs. It's easy enough and another feather in your cap being able to offer a value for money repair.

I hope other Saab owners find this useful. And with any luck this thread will come up in Google searches for CIM / airbag faults when distraught owners search.

If you've anything useful you can add, please do.

Regards

Cyd