987 Ventilated Seats Question for those WITH the option.

Hey gang - Working on a very obscure project, which is my attempt to add ventilated seats to my 987 Boxster. Definitely a very risky project in terms of expense, particularly assuming I cannot get it to work. I have a 987 Ventilated Seats Question for those who DO ALREADY in fact have the option, as I'm doing some testing here. My key question is this: If you put your hand over the exhaust that exits the lower back of the seat, do you feel the blower outputting a lot of air? Or is it just a slow speed motor that barely moves air -- where the effect is hardly noticeable? In my case, it's not obvious that it's working (and I haven't taken the car for a spin yet); the effect has been subtle in other cars I've been in. Apparently it's very subtle in the 987 from what I've read. I put a piece of plastic wrapping near the vent when the car was running and there was no movement -- which leads me to believe it's not running. Anyhow, I've realized that BOTH the seat heater and ventilation functions require the car to be running to actually turn on, and the blue lights on the button on the rare replacement climate control do light up when pressed. However, the issue is that the car's exhaust is so loud, I can't hear the seat ventilation motor turn on under the seat. I've swapped the seats, swapped the climate control, and coded the car to "see" the seats. The wiring harness plugs look identical to those of the heated seats, so hopefully it's not missing one or two wires in the wiring harness although the end plugs are identical. Again, fingers crossed that it is running (or I can get it running somehow) and I'm not stumped here. Thanks for checking your 987s for me!

I didn’t have it on my 987 but do have this feature on my 981 . The fan does not blow air out of the seats. It draws air into the seats and uses convection for cooling by pulling the moisture away from your body You will feel a much more noticeable effect if you’re a little sweaty and damp in the seat, but not so noticeable after your back and butt are dry. Seat ventilation is also in no way connected to the AC system which doesn’t even need to be turned on. It’s just a fan that draws air in through the seats, and in my case has three different speeds At high speed you can get a thin piece of tissue to stick to the seat back from the air sucking it towards it

That's great, @ICNU - I too have that in my 981, but it's in storage and can't verify right now. It's valuable enough that I'm trying to get that rolling on my 987. To clarify, you're saying that you can take a thin tissue -- put it on the leather seat back where your back touches the seat (not where the fan exhausts behind the seat) -- and it should stay in place assuming it's on the high setting. Correct?

Correct, that is how it works in my 981 when I was testing to determine the direction of air flow. I can also detect the sound of the fan running when on high in my car with the engine idling.

That's a huge help, @ICNU - A huge thanks. Clearly I've got more work to do here. Trying to find the correct wiring diagram for a 987.2 or a 997 that includes the ventilated seats.

Seth - as a WAG - the wiring isn't there. Porsche and BMW make "bespoke" wiring harnesses. They only include in the harness the wires necessary to power and control the equipment the car is sold with, with the exception of the occasional dealer installable option (which are now far and few between.) So, you'll have to find the wiring diagrams for the vented seat control systems, and see which wires are missing. Then figure out if it's worth buying the special tools needed to install the male/female contacts into the connectors to whatever controls them and to the connectors on the seats. Is it doable? Yeah. I've done sillier things (adding ABS on a BMW motorcycle that didn't come with it..) - just make it a winter project when it's too cold to drive the car, and start gathering the parts, and wires. Wire for Porsches is probably best bought by buying wiring harnesses out of Porsches at a wrecking yard. It would be hard to find the quality and size of the wiring Porsche used. Porsche occasionally sold "repair kits" for wiring connectors - that might be another avenue to explore. Good luck!

I have ventilated seats in my 987.2 and the fan is easily heard at idle. The convection sensation is quite noticeable as well. If it's working, I don't think one could miss it. I will check for air flow the next time I have the car out—probably later today. Best, George

@George_L - Thanks for checking! I'm now fairly certain the fans are NOT running; your checking is definitely a help and I'm looking forward to finding your definitive results. @deilenberger - As we discussed before I came down to NJ to pick these up, I feared that custom-built harnesses were exactly what had been installed. Given that (1) the wires (yellow connectors) coming from each seat are intact, (2) the specialized climate control is now installed, and (3) the car is now programmed to "see" the seats, by exclusion -- the additional wiring in the car must be missing. Boo-hiss!!! I just want to know WHY the heck Porsche omitted a few wires. Cost? Weight savings? I don't get it. Seriously! Maybe the wire harnesses are built on-demand by robots or something, so there's zero waste? Anyhow, what threw me off here was that the vented seats' yellow female seat connector looked identical to the previous set (heated only) at first glance -- and the seat heating did indeed work. What appears to be the situation is that the heated connects are indeed the same in both sets of seats... but the vented seats have additional connections as well. I'll have to disconnect the battery and the yellow connectors for another closer look. One breakthrough is that I FINALLY found very specific wiring diagrams that go to the 987.2 today via my PIWIS 2, and it's a question of deciphering it all. The key thing now is the feasibility of the whole project, and I have to make a quick judgment call about keeping the very expensive (and very hard to find used) climate control with the vent buttons or not -- or to build a home-brew and analog solution that wire up each seat. The former solution (the advanced climate control) would be my dream OEM solution. However, the climate control would be worthless if I can't figure it out -- and the non-functional buttons would haunt me. LOL! Now, engineering is engineering, and I'm no stranger to wiring things up. Given that we're talking about a set of four fans (two in each seat), a PWM switching system that involves the climate control (I think???) to change the speed, +12V, and a ground -- somehow I think it should be doable. If people could retrofit heated seats to their P-cars, my guess is I could ultimately figure this out as I believe it's a fairly simple system. @deilenberger - I had NO idea you put ABS on your R-bike when it was missing it. Now THAT is impressive. How are you at deciphering wiring diagrams? My guess is that I'll be able to figure out the 3-4 missing wires that come out from the yellow female wiring harness that plugs into the seat, run them wherever they need to go, and then somehow magically plug them in somewhere (tapping other wires/fuse box) --- but the climate control seems like a mystery per installing the right connector.

UPDATES : 1) Disassembling the MALE yellow connector that goes to a given seat has 100% CONFIRMED @deilenberger - his assertion that wiring harnesses are definitely bespoke built, and there's missing wiring involved in this case. This has been a question for years on the forums, and this is plain proof. I got lucky that the heated seats happen to work because the wiring is the same in both heated and heated/vented seats models. 2) I was able to determine from the actual connectors that pins 1,2,6,7 are indeed absent from the car's wiring harness (MALE yellow connector) and the heated seat connector (FEMALE yellow connector) as they were not built into either the car or the seats. However, they are present on the vented seats. 3) This also checks out on the wiring diagram (987.2). Pins 1,2 go to the climate control, and Pins 6/7 are for the fan (unclear where they go...maybe power and ground?). I'll need help from wiring gurus who can decode all the connectors and stuff for the wiring diagrams. I'm fairly confident with my ability to read wiring diagrams for 40+ years, but this is getting tricky. Inside the seat, Pins 1,2 are supposedly NTC+/NTC-, which I'm guessing must be for a thermistor? According to some Porsche literature, I believe the ventilated seats will shut off of they are too cold (to prevent condensation)? Meanwhile, I think Pins 6,7 control the fans -- and they already get their power from Pin 8 (same big pin for +12V). So hopefully I'm on the right track. (Yes, I'm so tempted to temporarily wiring up pins 6 and 7 to a low amperage +12V DC wall wart to see if the fans spin, but I don't want to fry anything as the PWM controllers appear to be built into the seats. 4) For all four missing female pins, my guess is that I should eventually be able to install the right female connectors into that connector -- assuming I buy some sort of tool and wires. Looks like a standard BMW/Tyco connector, so I'm guessing @deilenberger - "Terminal Pins For Repair Wire For BMW" is exactly what I'd need. But then, it's a question of where these four wires go...and then adding TINY female connectors to the right connectors on the climate control. That seems the most daunting of all.

Actually it was a K100RT that I did it to. I took an entire wiring harness from a later model K bike, removed everything that wasn't ABS related and ran it in parallel to the stock harness. I couldn't simply exchange harnesses (which was done on a 2nd K bike that went through this process) since the bikes had different wiring for normal functions (instrument cluster was a big one..) So I'd suggest you consider doing it that way. If the fan only needs 2 wires to power it, add a connector to the two wires for the fan on the seats (you could use Positaps to keep from damaging that seat harness), then run 2 wires to wherever the other end is supposed to go, and figure out how to connect them up. Easy-peasy. The big problem is the Porsche wiring diagrams - spread across typically 3 pages in a paper size that the US simply doesn't use. I prefer tracing things out with a highlighter and a printed diagram.

@foodbiker I appreciate the effort your taking with this project, and I'm pretty good with schematics (particularly unprinted ones) so if you need help deciphering I can help with that. All that said, I was also looking for a 987.2 with ventilated seats, but I never found one. I'd love to install it on my car, but I would not expend as much effort as you are on making it happen... maybe I'm just getting too old for that, haha. However, I would consider an "aftermarket" kit if something like that existed/worked. I don't have ventilated seat surfaces, so I imagine that won't work well for me... but that being said, I might suggest just wiring it up in a way that works, instead of trying to integrate it in like the factory would do. In any case, I'm interested to see how you fare... and happy to help if I can, even if I won't take on such a project myself!

Well, I didn't get the car out until today. In case you are still wondering, air does indeed exit the duct on the back of the seat rather forcefully when the ventilation feature is engaged.

@George_L - A huge thanks for checking. That is definitely a help, and good to know the fans are forceful when working correctly. Clearly mine are not operating right now and I'll know what to expect should I eventually get these to work. @deilenberger and @schwinn - A huge thanks, gents. I think I'm actually in good shape with the wiring diagrams, but will keep you posted if I get into trouble. @deilenberger - I cannot believe you did all that on a K100RT. I mean, I've done a lot of custom wiring on my R1200C to do a bunch of fun stuff, but adding ABS is taking things to a different level! *** Anyhow, after a few evenings of mapping things out, I think I've finally got it figured out, which is great. However, as I'm currently swamped with real-life responsibilities, I will likely take @deilenberger 's suggestion just to obtain whatever parts I need now and revisit the project later -- perhaps during the winter when I have more time. Again, my rushing to determine the feasibility of this project, has been driven by the brief return window of the exorbitantly expensive climate control unit that has the ventilation buttons. Although this is likely one of the most difficult projects I've encountered, it appears doable and I'm now confident enough that I've solved it -- confident enough to hang onto the unit. Thankfully, now I can step back for a bit and focus my attention elsewhere for the moment. This is clearly a 5-out-of-5 wrench expert project, yet I'm glad I'm tackling it and I hope my persistence will ultimately pay off. Assuming this works, ventilated seats will be the ultimately luxury addition to my 987.2 Boxster of 254K miles; I'll be very excited to make this happen if I can in the end -- particularly OEM style as adding external PWM controllers might be doable but less elegant. Used 987 ventilated seats are as rare as hen's teeth, as are used climate control units with ventilated functionality. Buying the seats in the first place was made far easier by @deilenberger -- as he was willing to vet the seats for me down in NJ and put me up for the night. (A huge thanks again for your help and hospitality, Don!) Yes, this continues to be a very expensive gamble of time and money for such an obscure project like this, but there will be something incredibly satisfying in believing that solid engineering is just solid engineering. Call me an idealist, but I'd like to believe that we can achieve superb results if we really want them.

So I have a 987.2 base and I have installed 997.2 power, heated and vented seats, I have also installed the temp controller which has the switches for vent, and like your car they light up but vent does not work. Have you sorted the pin configuration at the seat or are there other parts required or programming for that matter which needs to be done? I would like this to work like the factory option if possible. Thanks in advance!