M3Inline6

Spearheading the cause. Gotta appreciate threads like this.


P.S. Too bad you didn’t want to sell your LWBS.

f4bones

LOVE the LWCBs, but they get old fast for street driving. The biggest issue is the tilt - I've installed the tilt spacers that everyone uses - MUCH better, but still would be ideal to have adjustable tilt. So . . . . I ordered a set of seats out of a Panamera - they have the same rails, etc. My idea is to try and adapt the carbon shells to the electric rails, where it has one motor that lifts front, and one motor that lifts rear. It also has a 3rd motor for forward / aft. So for a weight penalty of less than 2 lbs, we would have fully electric seats. I'm 100% sure this will work - I've got one of my guys designing adapter brackets to mount the shell into the electric rails. The added bonus is that the Panamera seats had heating, adjustable lumbar, etc. I'm toying with adding these features, especially the air lumbar support, to the LWCBs.

Will of course post the project in a separate thread once it I have some concrete results, but I've disassembled the Panamera seats, and fit the shells into them, and it appears that they will fit nicely, with no additional height requirements (IE you won't lose headroom in mounting the buckets into the electric rails.

BTW, Panamera seats can be had used for around $250 complete so the cost of this entire project should be $500 - ish.

M3Inline6

Thats going to be an awesome project. I’ve never paid attention to Panamera seats, but now I need to take a gander.

f4bones

You wouldn't want to put Panamera seats in a 911, but they have lots of good parts, and the rails, motors, controllers, etc are the same as 991 generations seats from what I can tell.

M3Inline6

I took a look and you’re right. lol! LWBS’s it is!

f4bones

For those wishing do implement the VW 4M0 959 339 B PODs sensor, the mating connector is PN is 1J0-973-735 - available from Porsche for around $13, or Amazon for around $10 pre-pinned here -

f4bones

The crimp pins are TE PN 1241872-1 and the seals are TE PN 828904-2. Also, one can use the TE PN (493577-2) instead of the VW (1J0-973-735) PN for the housing, and they are $2.47 each. Pins are about $0.10 and seals are .05 on www.mouser.com . . .

M3Inline6

I ordered the VW part since you verified its compatibility.

f4bones

Great - the last few posts are for the connectors to wire them in. I'm still working on the best alternative for sensor pads as well. Once I figure it all out, I might put together a mini-kit with wiring harness pre-pinned to plug into seat plug - should be easy to do and will work with either OEM seats or aftermarket. . .

M3Inline6

That would be extremely helpful for us RennListers looking to upgrade to LWBS’s. This thread made everything less complicated.

SB27

Someone above said that you cannot swap 18 ways and LWB seats. That is false. I had both on a 991.2 GT3 and now on a 992 GT3. They are completely interchangeable but you lose the seat heating option (subject to the cool experiment going on here) if you ordered your 911 with LWB's installed first.

Hope this seat heater conversion project works successfully.

Great intel here. Thanks, gents.

stumil

Thanks to all for the wealth of information in this thread. Wouldn't it be nice if Porsche would just sell us the LWBS seats (at a semi-reasonable price) that we couldn't get for our cars during Covid due to supply chain issues? Those issues are gone now - Porsche should give us an option to buy the seats we wanted all along. OK, so that's not going to happen.

I have a 2023 718 Cayman GTS 4.0 with 18-way sofas that I'd like to track (and I drive my car to the track). I'm going to swap in Recaro Pole Positions during track season and swap back to my 18-ways for the other 8 months of the year. Can't I just buy another Control Unit for Seat Occupied Sensor (970-618-245-03), Seat Occupied Sensor (982-959-337), and whatever wiring loom I need, and have no airbag lights, and full functionality of all the airbags in the car (except obviously the thorax airbag that I think is part of the Porsche OEM LWBS seat)? Wouldn't this be the same as swapping in parts from a Porsche donor seat, or swapping parts with my existing 18-way seats? What am I missing here?

And yes, I am installing a CMS roll bar and Shroth harnesses along with the Recaro seats.

Thanks again!

f4bones

Absolutely. you can do this - there are a few things you will need for your Recaros - on the Drivers side, you will need a 3.3 ohm resistor between pins 16 & 17 to delete the airbag. Then you will need a position sensor wired to pins 3 & 10. On the passenger seat, you will need the same resistor between pins 16 & 17 to delete the airbag, the position sensor between 3 & 10, and then the PODs system wired to pins 11 (LIN), 12 (Supply) and pin 6 (ground, I think - this is only for the 991 gen), the 992 gen only has 2 PODs wires at the seat plug. Thus, you need to delete the aibags w/ resistors, install position sensors in both seats, and a PODs system in the RH seat and you airbag system will be fully functional w/ no lights.

Here is the pin-outs for both generation seats:

PIN 1 - Seat Heat Temp Sense
PIN 2 - Open
PIN 3 - Position Sensor
PIN 4 - Seat Power
PIN 5 - Open
PIN 6 - PODS (991 generation)
PIN 7 - Open
PIN 8 - Seat Heat Power
PIN 9 - Ground
PIN 10 - Position Sensor
PIN 11 - PODS (Supply, pin A9 on 992 Controller)
PIN 12 - PODS (LIN, pin A7 on 992 Controller)
PIN 13 - Seat Heat Ground (only on 991 seats - 991 has a separate ground for seat heat) - this pin is open on 992 gen
(numbering continues, but on the seat, it's a separate module within same housing)
PIN 14 - Seat Backrest Heat Sensor (992 only)
PIN 15 - Seat Backrest Heat Supply (992 only)
PIN 16 - Airbag
PIN 17 - Airbag
(numbering continues, but on the seat, it's a separate module within same housing)
PIN 18 - Seat Belt Switch
PIN 19 - Seat Belt Switch

As I mentioned in a prior post, the GT3s that came with LWCBs didn't have the wiring for seat heat, nor the wiring for the seat heat switches. You can purchase the harness for the switch in the console (addressed above), but to add the wires for the seat, you need add wiring from both seats to BCM1 - it's located just above the driver's side fuse box under the dash:

From Drivers seat:
P1 to BCM1 B23 (heat sense) - 22 AWG White / Yellow
P8 to BCM1 B71 (heat power) - 16 AWG Green / Blue
P14 to BCM1 B25 (heat sense) - 22 AWG White / Blue
P15 to BCM1 B72 (heat power) - 18 AWG Green / Yellow

From Passanger seat:
P1 to BCM1 B26 (heat sense) - 22 AWG White / Red
P8 to BCM1 B11 (heat power) - 16 AWG Red / Gray
P14 to BCM1 B27 (heat sense) - 22 AWG Green / Brown
P15 to BCM1 B10 (heat power) - 18 AWG Red / Yellow

I've ordered the correct color striped wires, and some old connectors to try and figure out the correct pins / terminals - worse case I'll have to butt-spice in the terminals if I can't figure out the PNs for new crimp terminals. Either way, once wire and old connectors get here, should be a pretty easy task to add these wires, and we will have seat heat!

stumil

f4bones, I want to have your baby! You completely rock! Many thanks.

stumil

f4bones - you didn’t mention having to do any PIWIS 3 coding in your solution post to my Recaro swap question. I assume no PIWIS coding will be needed?