Steering Wheel - removal and refitting
1 ) Park the car with the front wheels in the straight ahead position
2 ) Open the bonnet and using a 13mm spanner / socket disconnect the battery (both terminals). I usually place a small plank on top of the battery and rest the cables on it, just to be sure.
3 ) Because the SRS system has a batery back-up, you need to leave the car for 15 to 20 minutes to allow it to discharge fully. There is a very
small risk that any residual current in the system could trigger a deployment as the air bag is disconnected. I know of people who regularly work on the SRS system 'live' and have reported no problems, so the risk is small, but the workshop manual recommends the above proceedure for safety reasons - i always follow it anyway.
4 ) Using a T30 Torx bit, undo the two airbag retaining bolts. These are sited in recesses on the back of the steering wheel (they feel like slots)
Remove the 2 T30 Torx bolts that retain the airbag
5 ) Carefully withdraw the airbag, reach behind it and unplug the yellow wire.
All SRS wiring is colour keyed yellow
Place the airbag pad side up and away from anything flammable. Also, never put anything on top of the airbag pad. In the case of a deployment the airbag can fly across the room (if placed pad side down), or propell other objects across the room (objects placed on top of the pad). Lastly airbags are deployed using explosives and are also covered in a fine layer of talc - both of these items can cause fires.
Sorry for sounding a bit heavy here, it's just basic common sense really and the risks are very small, but by the same token i'd hate to see anyone get hurt.
6 ) Unplug the horn multiplug from the rotary coupler.
7 ) Using a 19mm socket on an extension, undo the central lock nut.
This is the main retaining bolt for the steering wheel
Tip! I find this is easiest if i grip the steering wheel with my knees as well as my left hand, then turn the ratchet with my right hand.
8 ) Withdraw the steering wheel being careful not to turn the spline, or the rotary coupler.
Note, if you accidentally turn the rotary coupler (easily done), here's how to re-centre it.
Wind the coupler fully in one direction, then slowly wind it back the way you came, counting the full rotations as you go. From memory it's about 7½ turns to get all the way to the other end of the tape, but you should do this yourself here, wind slowly and count the full revolutions.
Divide your total revolution in 2 and wind the coupler back this many times, the connection for the multiplug should now be close to, or at the right position to accept the steering wheel.
Refit the wheel on the spline, being careful to get it straight (this is why the road wheels need to be in the straight ahead position).
Refit the 19mm lock nut (tightly, not sure what the correct torque here should be but i do them as tight as i can get - torque of 'Owww'
Plug in the horm multiplug
Plug in the airbag and position it in the steering wheel
Refit the T30 torx bolts
Reconnect the battery (both terminals)
Switch the ignition to position 2 and check that the SRS light comes on, stays lit for a second or two and then extinguishes.
If so then all is well!