Description: I still love my 2006 CS with Tiptronic, but over the last couple of years, I have thought that the 987.1 style Tiptronic steering wheel with the triangular airbag, was starting to look a bit dated. I have also long wished that the car came with a traditional paddle-shift steering wheel, rather than the older style Tip buttons.
I was aware that some 1st generation Tip owners had successfully swapped their old style steering wheels, for the sport wheel with paddles, however, the cost of buying both the steering wheel and the round airbag (usually sold separately) had been too expensive for me to consider - especially since it is more a matter of taste than a performance enhancement. However, I recently had the opportunity to buy a take-off steering wheel airbag from a newer model Cayman S or R that was being converted to a race car, at a very reasonable price (as Porsche parts go).
After doing a little research online, and consulting a fellow Cayman owner who had made the swap a couple of years ago, I discovered that I would also have to replace the electronic steering control module located in the steering column, in order for the paddles to work. This part (PN: 997-613-289-01) was unfortunately another $250 or so from my favorite online parts supplier. Finally, I was hopeful that I would be able to use my Durametric Professional Cable to enable the wheel to work - alas, this was not to be the case, and so it took an hour of PIWIS/labor time at my local dealer to get it to work. More about that later.
NOTE: THE FOLLOWING PROCEDURE IS FOR DEMONSTRATION PURPOSES ONLY!! THIS MODIFICATION INVOLVES TWO CRITICAL SAFETY FUNCTIONS OF YOUR VEHICLE: THE STEERING AND DRIVER'S AIRBAG. IT IS RECOMMENDED THAT YOU ALLOW THE DEALER TO PERFORM THIS MODIFICATION. IF YOU CHOOSE TO PROCEED ON YOUR OWN, YOU SHOULD CAREFULLY FOLLOW THE PROCEDURE AS OUTLINED IN THE CAYMAN SHOP MANUAL, AND YOU UNDERTAKE THIS AT YOUR OWN RISK!
Small flat blade and/or torx screwdriver or punch
M-12 triple square drive and socket wrench with extension
T-8 and T-10 screwdrivers
4 mm hex key
New steering wheel screw (PN: 910-207-01) or thread locker
Steering Control Module PN: 997-613-289-01
1. Turn key in ignition to position to unlock the steering wheel. Make sure front wheels and steering wheel are aligned straight ahead. Turn off ignition key. Then disconnect the battery (negative/ground lead is sufficient). You should then wait at least one minute to allow for airbag system to be completely disarmed, before you proceed to remove the airbag.
2. Remove Airbag - see pictures below. There is a small hole in the bottom of Porsche steering wheels that is used to release the airbag. Insert a small flat blade or torx screwdriver, or a punch into the hole until you hit some resistance about 1" in. This is the bottom of the spring-loaded wire retainer that latches onto the airbag from the rear. You must push up on it to release the airbag. If you are using a flat blade screwdriver, make sure the blade edge is oriented fore and aft, since you are trying to hit the spring wire going across the bottom. Depending on the quality of the springs behind your airbag, it may just pop free easily, or you may have to pull and/or wiggle it a bit to get it to come free.
3. Disconnect Airbag - Once it is free from the steering wheel, you will see two colored wire connectors (green and yellow) connecting the bag to the steering wheel harness. You must pry up the locking tabs with a small screwdriver to remove them. Disconnect the horn wire by pressing on the small locking tab on its connector, and the airbag is now free. Set it aside in a safe area.
The horn wire connector is shown below - the newer model round airbags only have a single ground wire connection, which is probably why the horn won't work unless you change the control module also.
4. Remove Steering Wheel - First, disconnect the harness connector inside hub. Then, using a M12 triple-square drive (which I bought at a local Autozone) with 1/2" socket and ratchet, remove the screw holding the steering wheel in place. Note: the OEM screw has a micro-encapsulated coating which acts as a thread locker, so breaking it free may require some strength, and you have to hold counter-rotation on the steering wheel.
You can see the "micro-encapsulated" coating on the steering wheel screw below:
For those who are just swapping a steering wheel by itself, you can then proceed to Step 8. If you are upgrading a Tiptronic to paddle-shift steering wheel, you must now remove and replace the module which is located in the steering column.
5. Removing the steering electronics control - First, remove the steering column trim: there are 3 small recesses on the bottom of the steering column concealing T-10 screws (circled in red below) - remove all 3 screws. There is an additional retaining clip on the inboard side which holds the upper and lower halves together - I didn't bother to figure out how to release it. The shop manual diagrams show the trim completely removed, but I was able to remove the whole steering control unit by opening the 2 halves like a clam shell. You must also loosen the retaining screw (4 mm hex drive circled in blue) which holds the steering unit in place (Note: it isn't necessary to completely remove it). Finally, there are 2 wiring harness connectors (yellow airbag and black electrical) on the top, back of the control unit that must be disconnected using a small screwdriver to press the release tabs, before you can pull the steering unit off of the steering column.
Use a 4 mm hex wrench to loosen the retaining screw on the bottom of the steering control unit.
6. Replacing the control module - Take the whole steering unit to a workbench or area where you can work on it. The module your are replacing is on the back (i.e. towards the front of the car) of the steering unit. It is held in place by 5 torx screws which are concealed by the airbag contact unit on the front (closer to driver) part of the unit - so this must be removed first. It is held in place by 5 small retaining tabs (2 on top, 1 on each side, and 1 on the bottom). Carefully pry up the tabs while pulling the airbag contact unit away from the rest of the unit, until you are able to separate the whole thing. You will now see the screws (circled in red below) that you must remove to disconnect the electronic module. You may now connect your new module, making sure to fully seat all electronic connectors, and reassemble the steering unit in reverse order.
The picture below shows the whole steering unit with the airbag contact unit facing up.
NOTE: The shop manual emphasizes the importance of keeping the small triangular pointer (circled in red above) on the face of the airbag contact unit, aligned between the 2 curvilinear markings on the plastic (indicated by red arrows) during the whole process of removal and re-installation, or you may cause failure of the airbag when re-installed improperly.
You must disconnect the connector circled below on the control unit, prior to removal.
The locations of the 5 T-8 screws holding the control module to the rest of the steering unit are shown below.
7. Replace the steering unit - being careful to reconnect the 2 wiring connectors, slide the module back onto the steering column until it is as far forward as it can go, and re-tighten the 4mm hex retaining screw at the bottom of the column. Replace or reposition the upper and lower halves of the steering wheel trim to make sure it is all buttoned-up properly, and replace the 3 small torx screws from the bottom.
8 Replace the steering wheel - Slide your steering wheel onto the column taking care to make sure it is aligned to the straight-ahead position. If you are off by even 1 notch on the connector, it is pretty noticeable when you start driving (don't ask how I know).
It is recommended that you replace the used steering wheel screw with a new one, because of the one-time use micro-encapsulated coating. I elected to use some blue (non-permanent) thread-locker instead. Applying counter-rotation to the wheel, tighten the screw to 37 ft/lbs of torque.
9. Replace the airbag - First, connect the electrical wiring harness connector in the back of the hub, then connect the 3 wire connectors (yellow and blue airbag connectors and horn ground wire). Making sure that you have the airbag oriented correctly, push it back into the steering hub until it clicks into place.
10. Making it work - Unfortunately, this is where this falls short of a complete DIY project (unless you have access to a PIWIS computer). I had hoped that I would be able to activate the steering wheel with my Durametric Professional cable, but unfortunately, it wouldn't recognize the new control module,and it appears from the shop manual that some additional programming is involved whenever you change the electronic control module. I was able to re-calibrate the steering angle sensor, and clear an error code created by the swap; however, the paddles wouldn't work.
So, it was off to my local dealer to try and convince a slightly dubious service adviser that it should be possible, because other owners had done it successfully. It ended up taking over an hour with 2 or 3 service techs collaborating to figure out how to make it work - they finally discovered that they just had to ignore the error message they were getting when attempting to program it, and it worked. They ended-up charging me an hour of programming/labor time, but I was relieved that it finally was working.