Rewire Steering Wheel PDK Buttons? - 2010 Cayman

I have owned my 2010 Cayman S for just over a year now, and I still have yet to get used to the steering wheel push/pull buttons. In competition events I sometimes accidentally press them and get unintended upshifts. And in normal driving I still fumble with pulling when I mean to push. What I would like, is to have them behave like paddle shifters - pulling on the right upshifts and pulling on the left downshifts. Pushing on either does nothing. Is this something anyone has done before and might provide input from experience? I've searched on the forum and internet in general, and found lots of stuff about replacing the steering wheels - but so far nothing about changing how the PDK buttons behave. I can imagine accomplishing that by either re-wiring the connector from the steering wheel or at the switches themselves. This is the style of steering wheel I have:

i am going to try this - just ordered the kit Works Bell Paddle Shifter & Short Boss / Hub Bundle For Porsche Cayman PDK - The Tuners Group

actually this is the exact link to the kit Works Bell Paddle Shifter NEO And Works Bell Rapfix II Quick Release Bundle, Plus Short Boss / Hub For Porsche Cayman PDK - The Tuners Group

That looks really nice. So does this kit from Champion Motorsports: Champion Motorsport - Porsche PDK Paddle Shifter Conversion But both are pretty darn expensive. I dont have a problem with the shift buttons themselves, but would rather they worked like the paddles with pull right/left rather than push-pull on either. Seems like there should be an inexpensive way to get them to behave differently.

I think this can be done, the tech art paddle conversions for your style wheel changes the action to match what you describe. It is a combination of new buttons with paddles and some re-wiring.

For what they're charging for these conversions, why not just buy the paddle shift wheel from Porsche , it's going for $1K. Steering Wheel - Paddle orsche Parts & Porsche Accessories - Wholesale Porsche Parts & Tequipment

This. Even less if one keeps an eye out for used ones. And the swap is a total cinch.

Thanks for the replies! My goal is not to spend a lot/any money. But I am a little dissapointed finding info in this thread that describes the system as using a CanBus system so you cant just re-wire the connector: http://www.planet-9.com/981-cayman-boxster-modifications/88099-reversing-manual-mode-pdk.html I also did stumble across some info that suggested it was possible to re-map the buttons with PIWIS - but I'm not sure if that was just speculation: http://www.planet-9.com/987-cayman-...-cayman-boxster-modifications/48750-pdk-steering-wheel-button-modification.html

One of my most enjoyable mods was buying a mint condition oem paddle wheel on fleabay then sold push button wheel. Easy install, no problems. Now I use the paddles to shift almost 100% of the time.

Success!!! I found detailed instructions for disassembling the steering wheel, posted by folk who were replacing the T-shaped trim with the multifunction button trim. After taking it apart and examining the circuitry for the shift buttons its clear that it sends Up/Down Shift signals to the car without indicating which button (left/right) was used – so the ideas of PIWIS coding or swapping wires downstream from the wheel are not possible. But the circuits are really simple and I modified mine to work the way I want. Its all back together now and its great to have the buttons work like paddles. I will post the step by step photos and steps I took, but its definitely not for the faint of heart. You have to pry the wheel apart, disconnect one wire from the left side circuit board, and then (gulp) break some traces and solder a new wire on the right hand circuit board.

That's great news. looking forward to this!

Really excited to hear that this works! Can't wait to see the step by step! If this works well, it should be the cheapest "paddle" shifting conversion available.

Here are the steps I took to rewire my steering wheel. I'll try and describe what I learned and hopefully it will help other people. I need to try and make it clear up front - YOU COULD VERY EASILY DAMAGE OR RUIN YOUR STEERING WHEEL. There are a lot of small delicate parts that seem to be intentionally made easy to break while disassembling and working with the internal components of the wheel. I'm happy with the final result of my attempt, but it did not go perfectly - and I did break a few pieces here and there. I'll outline where things went wrong for me and hopefully people can do learn from that and do a better job knowing where I made mistakes. Part of me feels like there should be a disclaimer saying this information is for "entertainment purposes only". GOAL: Get the PDK buttons on the stock steering wheel to behave like paddle shifters. Pulling towards you on the left to shift down and pulling on the right to shift up. Pushing away from you on either should do nothing. TOOLS: T55 Torx socket, small torx driver, really small torx driver, blade screwdriver, two knives, ohm meter, soldering iron, xacto knife, electrical tape, very thin solid core wire, solder. Here is the wheel at the start, it works fine but I dont like the way the buttons shift. I've never gotten used to the push/pull and in competition events I've accidentally pressed on a button while turning and had unintended up-shifts. The sport paddle shift steering wheel would be very nice, but its expensive. I did this whole project with tools and materials I already had on hand. 1. Disconnect the battery. This is an important first step since the aribag needs to be taken out, and we really want to minimize the chance of it deploying. If you do the whole procedure and re-connect the airbag before putting the battery terminal back, you should be fine - but if power is restored without the airbag you will get a dash warning light that can only be cleared by the dealer or a OBD/Durametric tool. DO NOT CLOSE THE HOOD AFTER DISCONNECTING THE BATTERY - the mechanism to open it requires power. 2. After waiting a few minutes push a blade screwdriver through the little hole at the base of the steering wheel. Inside there is a spring loaded metal bar that holds the airbag in place. When you push it up, the airbag is released and will pop out. 3. Pull the airbag unit out carefully and be sure not to stress the wires that connect to it. 4. The orange plastic tabs need to be popped up for the terminals to be removed. There is also a ground connector that just slides off.

5. With the airbag out of the way you can reach in and disconnect the wire block that goes to the car. Press down on the orange tab at the top to get it to come off. 6. I used a T55 Torx socket on an extension with a ratchet to remove the bolt that holds the steering wheel in place. 7. The bolt came out fine, but it did have some blue locktight from the factory and it was a little tough to get it started. 8. Mark the top of the steering wheel and the shaft. The steering wheel housing has a notch at the top, but I needed to make a corresponding mark on the shaft to be sure I was putting it back properly (its not keyed). 9. It felt a little weird to be in the driver's seat with no steering wheel. And h ere is the wheel out of the car.

10. Once the wheel is out of the vehicle, its time to start taking it apart. The instructions I found suggested using two knives and a blade screwdriver and advised wraping them in tape to help protect the surfaces you will be using them on. 11. The spring that holds the airbag release wires in place needs to be relieved. Once the spring is off, push the wires to the top of their travel since they need to be able to come out with the plastic trim. 12. The PDK shift buttons have two pieces that snap together. The way I separated them was to use a knife on the side where they touch and my fingers on the other side. You have to apply a good deal of pressure to get it to come apart, and try to apply reasonably consistent pressure on both sides. 13. Once the button backs are removed from both sides it reveals four of the really small torx screws that are really attaching the rear to shafts that go to the front pieces. I dont know exactly which size torx screws they are, my little kit doesnt have labels on the bits... Also make sure that the airbag release wires are up high enough to come off of the steering wheel base.

14. With the screws removed you can see that the buttons are really the little plastic nubs and they get pressed by part of the plastic housing. 15. The front part of the button will come off at this point if you press on the shafts, but I broke a little tab on mine that was holding it in. When I went to the left one I could see the tab and thought if I used the knife I could get enough clearance to pull the button off but I ended up breaking that one too. In practice I dont think they are critical since that whole assembly is screwed together - and I think you need to get the buttons off before the wheel will come apart - but perhaps there is a better order of operations to get it apart without breaking the little tabs. 16. Now on to what was the biggest leap of faith for me - prying the grey plastic trim off the steering wheel. There are 8 plastic "rivets" that need to be relieved for it to come off. They are white plastic/rubber bits that fit into holes in the solid part of the wheel. Mine were really tight and I had to pull so hard I was sure the whole thing was going to snap. Luckily it didnt, but I did break one of the rivets - on the far left side. The others all came out okay. Look at the picture below to see the position of all of them to have a sense of where to put the pressure. It works best if even pressure from both sides is applied. Look carefully to see where the rivets are:

17. Starting with the two in the bottom of the center piece seemed reasonable. The picture shows where I got the knives to start making a gap, but the place I ended up applying the pressure was closer to the bottom between the leather and the plastic. When the rivets come out its pretty obvious and they gap stays open. 18. Doing the ones on the sides is also nerve wracking, especially since I wasnt exactly sure where was the right place to apply the pressure. Sticking the screw driver in above the buttons to do the ones on the inside first and then do the one on the edge worked - except for the left side where the last one I was working with snapped off from the trim.

19. Once the trim is separated from the wheel we can move on to the actual task of re-wiring the buttons. 20. There is a circuit board for the right and left side, three torx screws hold them under their plastic housings. The wires that connect the two circuit boards for the buttons run along the center of the wheel with the wires for the airbag. I took this picture to help me remember how the wires went when it was time to put them back. 21. Removed from the trim and the rest of the wheel, these are the two circuit boards that support the PDK buttons.

22. This is the one on the left, and is the easy one since pulling towards you already shifts down. All that really needs to happen is to remove the connection for the upshift button. I somehow managed to not get a good picture of it, but what I did was simply pull out the 4th wire from the connector and wrap it with electrical tape to keep it from shorting on anything and then wrapping it to the other wires. You could also snip the wire I suppose. 23. The one on the right side is more complicated because one button needs to be disabled, and the other one needs to send a different signal. The downshift needs to get cut and the upshift signal has to be wired to the buttons on the back. 24. I used a meter to figure out which wires go where. Going from left to right on the connector as it faces us, the signals are: 1=Ground 2=Light Power? 3=Downshift 4=Upshift So really the only thing we need to do for the left side is remove the #4 wire from the connector. 25. The right hand side circuit is where the most needs to be done. On the face, the button that used do do downshift needs to be re-wired. I did that by first cutting the trace that goes to it at the > mark. Its important to do that above the through hole so the rest of the signal path for downshift remains intact. You can see I made a mess on another part of the board below the cap, dont worry about that I was confused when I did it - my intention was to break the line that took signal for upshift to the left side - but that was before it occurred to me that I could just disconnect the wire and didnt need to mutilate the circuit board. 26. On the other side of the circuit board I cut the trace that took the upshift signal to the buttons at the > mark. Then did the first solder connection with a piece of thin solid core wire in the through hole for the upshift signal. My wire was just thin enough to go through the hole, and my approach was to dab a bit of solder on the wire behind the tip and then heat the through hole with the soldering iron on the other side so that the solder would melt as the wire pushed through. That seemed to provide a good solid connection. 27. To connect the upshift signal to the button on the other side I used the through hole shown here but needed to cut away a bit of the rubber to get access to the hole. It was also important to make sure that the wire did not stick too far through since the rubber on the other side needed to have a good smooth contact around the buttons.

28. At this point is really important to test the connections and make sure that the signals are getting sent the way they should when the rear buttons are pushed, and confirm that no signals are being sent when the face buttons are pushed. I reconnected the wires and used the meter to make absolutely sure everything was solid and behaved correctly. The small four wire connectors on each board are like so: 1=Ground 2=Light Power? 3=Downshift 4=Upshift The larger eight pin connector on the right circuit board is: 1=? 2=Ground 3=? 4=? 5=? 6=Downshift 7=Upshift 8=? Use a meter and confirm that these signal/pin assignments are correct and you have made the proper modifications to get the buttons you want shifting properly. IF IT DOES NOT SEEM TO BE WORKING TESTING IT ON THE BENCH, IT WILL ALMOST CERTAINLY NOT WORK IN THE CAR.

29. The circuit boards back in their housing s, reconnected and re-routing the shift wires with the airbag wires gets the grey plastic trim piece ready to go back on the steering wheel. 30. Pressing the trim rivets back into the wheel has a really satisfying feeling when its all snug again. Even though one of my rivets did break, it still feels solid on that side - but I could see using some glue if parts were prone to separating. 31. With the plastic trim back on make sure the wires that secure the airbag are lined up and snapped in properly. Particularly make sure the pieces highlighted in purple are snapped in - if they are not, the airbag will slide in but it wont move in and out the way it should for the horn. 32. The wheel all back together and ready to go back into the car. 33. And done.

And just to make sure due credit is given, most of the disassembly information I got came from this thread: Multi-function wheel upgrade for 997.2 - Page 2 - 6speedonline.com Forums If I wasn't able to get the steering wheel apart, I clearly would never have been able to re-wire anything...

I think you can do this by re-arranging the wiring of the 8 & 4 pin plugs on the RHS board, without any work on the LHS board as follows: Connector A – 8 cables 1=? 2=Ground 3=? 4=? 5=? 6=Downshift (pull) 7=Upshift (push) 8=? Remove wire connected to Pin 6 of connector A. Remove wire connected to Pin 7 of connector A & install in Pin 6 slot of connector A (enables upshift function for pull of RHS button only). Note: There will be no wire in Pin 7 of connector A, effectively disabling “push” functionality of RHS button. Connector B – 4 cables 1=Ground 2=Light Power? 3=Downshift (pull) 4=Upshift (push) Remove wire connected to Pin 3 of connector B & connect to wire removed from Pin 6 of connector A & insulate (enables downshift function for pull of LHS button only). Remove wire connected to Pin 4 of connector B & insulate (effectively disabling “push” functionality of LHS button).

Yes, that should work.

Nice job on this. One question...I see that there 6 pins on the connector from the wheel to the steering column. Did you check the outputs to see if the left and right paddles were kept separate (ie. the up shift signal from each side were not combined to one wire going out) and that the pins were: Grnd, Light, Left Upshift, Left Downshift, Right Upshift, and Right Downshift. If that were the case you might simply make the changes to the wiring in the connector and not bother with going all the way into the boards?

Sadly that is not the case. The signals that go through the connector to the steering column are just shift up/down. It doesnt pass along which switch initiated the shift.

Robertsmania, Kudos to you for undertaking and writing up this intense modification. Several questions for you: 1. Are you still enjoying this modification? It seems that the buttons would be more responsive than the paddles. 2. As per fontana302 suggestion, are the wires in the multi-connectors re-configurable? 3. With the battery disconnected and airbag out, do you think it possible to remove the grey plastic trim without removing the wheel and buttons first? Or, are removing the buttons required to access the trim mounting pins? 4. To prevent the rivets from breaking, do you think it more important to have the prying tool in and up towards where the rivets are attached to the trim or, is strong pressure on equal sides of the trim enough to dislocate the rivets? 5. Any other tips or advice? Thanks, -Stevie

Thanks for posting! 1 - Yes, I still enjoy having the buttons work this way. It seems much more natural and I no longer have the occasional accidental upshifts when my palms press forward on the buttons in competition situations. 2 - I have not taken mine apart to re-wire it the way fontana302 suggests in post 24, but I do believe that is a valid simplification and would allow you to get the same result without modifying/soldering the way I did it. 3 - I think you do need to remove the wheel and buttons before getting the grey trim off. 4 - Having the proper tools for the job is always advisable. The tape wrapped knife I used to pry was probably not the best and if you can focus the force around the rivets, that would be good. But mine did come apart pretty well with force applied where I could with the knife. I'm pretty certain that the one rivet that did break for me was from being twisted while working on getting the other side loose before it was fully relieved. 5 - This style of steering wheel does seem to be available on ebay in the $200-300 range pretty regularly. When I did the project I figured I could get a replacement wheel if I really messed it up or it didn't work out. If you are concerned about it, perhaps buying a spare wheel initially and doing the operation on it would lower the risk even more?

Very clever! Great post and DIY but I really wish that people would stop advertising the T55 Torx as the correct bit for removing the wheel. It is an M12 triple square, not a T55 Torx. If you have to buy the tool, get the right one. - Patrick

Thanks for your contribution. I no longer seem to be able to edit the previous posts in the thread to make the clarification. The T55 I have does work, but clearly its better to always use the proper tool.

@Robertsmania - thanks for this pioneering work - could not have done this without you. I followed the wiring above and after cutting off the crimped connector ends from the wires removed from the connectors I crimped them together and covered with heat shrink. Yes you can remove the wires from the micro connectors - connector tools help but you basically push the metal tab flat and pry up the plastic finger that engages the said tab and pull the wire with crimp end out of the connector body. Y can also re-install the #7 wire into the #6 slot. I used this pry bar - they are sold at Harbor Freight. I followed the instructions herein up to a point. First I was able to loosen the two fasteners in the lower spoke. At this point I was able to put my fingers under the lower spoke as shown and "pry" the plastic away from the wheel. As you can see I did not need to remove the front buttons. Until you remove the plastic facing from the wheel you cannot remove these front buttons without breaking a tab. In fact you never need to remove the front buttons. Using After you pry up so that the lower spoke plastic is about 1/2" away from the wheel, use the tool to pry up the left and right spoke ends. Once they noticeably move, go back to the position shown above and keep prying. Go back and forth between these modes and the plastic will "rotate " off the wheel. I was bale to extracate it without breaking any fasteners.