Starting the process of installing 997 seats in a 997

[KevinH1990]

I know I am taking a risk, but yesterday was my birthday and I decided to buy these seats:

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The seller claimed they are from a 2009 997 with 51,000 miles.



They have all the options I wanted including heat.

There is a post on Rennlist in which a member named Floridaman said he was able to make seats like this work: https://rennlist.com/forums/997-forum/1279635-18-way-power-seat-test-help-2.html#post18593747

Although other members had issues.

As Floridaman recommended on Rennlist, I also have the pigtails from the car.



The less complicated side (I assume it is the passenger) is mostly power and ground.



The twisted wires are most likely the CAN high and CAN low which is for the memory.**** I am assuming anything predominantly brown is ground and predominantly red is power.

I have a computer power supply that I can use for 12-volt power.**** My plan is to use this to power the seat and experiment until am comfortable with my understanding of how the seat operates.**** I hope that I am as fortunate as Floridaman and have working seats without too many complications.****

There is a good series of videos on YouTube showing how to connect the seat heaters from 997/987 seats and make them work with 986/996 controls.**** I'm not planning to make use of the CAN bus, so I don't expect to make to be able****to make the memory work.

I welcome comments and suggestions.

[KevinH1990]

http://986forum.com/forums/diy-project-guides/79200-diy-heated-seats.html

Here's a link to the TT Gators instructions that I will be following to adapt the 987 seat heaters to the 986 controls.

It appears that STL986 contributed to the development of the necessary equipment. See post #14 in the thread.

[husker boxster]

Happy birthday! Great project.

[KevinH1990]

Originally Posted by husker boxster

Happy birthday! Great project.

Thanks. I have some experience with seat upgrades. I started with unheated, two-way power seats in my Boxster. In a series of steps, I upgraded to a heated 12-way power seat with memory on the driver's side and a heated 8-way power seat on the passenger's side. The DIY I wrote describing the process is too large to upload to this forum, but I posted them here:
https://rennlist.com/forums/boxster-and-boxster-s-986-forum/938572-memory-seats-option.html

I also installed some C63 AMG seats in my daily driver 2005 Mercedes C230. It took me a very long time to figure out the electronic controls, but I was able to make it work: https://mbworld.org/forums/c-class-w203/716541-seat-swap-2009-c63.html#&gid=1&pid=12 I went in several wrong directions before I achieved success.

I thought I would be eternally happy with the upgraded seats in my Boxster, but they suffered in comparison to the C63 seats.

I hope that the knowledge I gained from the previous projects and the comments from members of this forum will contribute to the success of this endeavor.

[KevinH1990]

https://rennlist.com/forums/997-forum/1035404-seat-swap-memory-comfort-to-non-memory-sports.html

This thread appears to contain a clue to the function of the driver's seat.

[KevinH1990]

Because the driver's seat is the most complicated component I decided to explore it first. The system that operates it seems similar to the system that is in my C63 seats. It also has some characteristics of the 986/996 memory seats in my Boxster.

The seat connects to the car with two harnesses. One is connected to the seat using a large yellow connector. The other connects to the computer module under the seat:





The harness that the recycler included when I purchased the seats appears to be from a car equipped with different seats. The yellow connector fits fine, but the second connector on the harness does not fit the computer module:


You can see in the top right that the second connector is almost square compared to the rectangular socket on the computer. The recycler must have given me the pigtails from a different car.

I plan to contact the recycler to see whether they can send me the correct harness.

I connected the power and ground of the yellow connector to a 12-volt power source. As I expected this did not allow the seat to work. My theory is that I also need to provide power and ground to the control module. I expect that the largest terminal on the computer module is the power and one of the terminals next to that is the ground, but I am proceeding with caution to avoid damaging what is likely to be an expensive component.

You cannot see it in any of the photos, but like the memory seats in both my Boxster and C230 Mercedes, each seat motor in the 997 driver's seat has 4 wires connected to it. One set of two wires provides controls the seat motor from the memory and the other two provide control from the switches on the side of the seat. If the seats are like the ones in my C230, the air bladders in the bolsters and the lumbar support are not controlled by the memory.

There are a total of 4 sockets on the control module. In addition to the empty socket that attaches the module to the car, there is one that I expect has connections to the seat motors. There is also one that connects to the controls on the side of the seat. I need to determine the function of the fourth connector.

I also tested the passenger seat. Supplying power and ground to the connector is all that I needed for the controls. I will need to follow TTGator/STL986's guidance for the seat heaters.

I'll continue to explore and post updates as I gather more information. Please feel free to pass on suggestions.

[Stl-986]

Pass side for all the seats is easy. there is no canbus controller for it. heat is just a 2 wire +12v & gnd and seat power is the same. Driver is same for heat. but not for seat power

Seats with 8way or more are a royal pain and you have to do a lot of removing the wires & soldering new ones plus removing some of the traces on the circuit board where the switches are. It is not an easy project. Took me a month pouring through documents, schematics and lots of trial & error. Had a whiteboard that was a complete jumble of things to keep track of it. Finally got it all done and after decided that it was too much of a pain to document.

I would recommend sticking with 4 way seats even though I love the 12way seats. If I did it again I would wait to find a set of 4 ways. I barely drive any of my cars anymore and will put my 2000 up for sale if anyone wants it. $5k and it's yours...with the 987 seats & 03 glass top.

I did start on a much smaller circuit board a few months back but have been spending most of my time on a new business venture. I'll get back to it eventually and then all my new boards will be the new version that is much much smaller then the existing one I make.

[KevinH1990]

Thanks for for the response. I have read the Pelican/101 guide to installing 987 seats in a 986. I have also seen some threads on Rennlist that suggest other methods might work. The Pelican/101 method is my backup plan in the event I can’t find a simpler or more elegant solution.

The C63 seats I installed in my Mercedes seem to share many similarities with my 987 seats. I initially found a way to work around the CAN BUS on my Mercedes, but eventually someone provided additional insight and I was able to integrate the memory and some other features into the car.

A key difference between Mercedes and Porsche is that Mercedes like mine are common at the “Pick and Pull” near me. I was able to see the components in a vehicle and buy inexpensive parts. Porsches seem to be scooped up by specialists recyclers.

I will continue to post updates. If I appear to be heading in the wrong direction, please don’t hesitate to provide feedback. I may be working on this off and on for several weeks.

[KevinH1990]

Everything works on the passenger seat, but I'm continuing to struggle with the lumbar and side bolsters on the driver's seat. The problem may be a defective air pump. I decided I wanted to use the seats during the prime top-down weather in the Fall. I will decide whether to replace the pump during the winter.

[KevinH1990]

I am continuing to work on the lumbar and side bolsters in my driver's seat. I had previously replaced the lumbar/bolster pump with a used one. I tested the pump I removed by applying power and ground to the motor, and it did not work. I saw a You Tube video posted by a Corvette enthusiast. He showed how the Corvette lumbar pumps stopped working because the fan that creates the air pressure jammed due to gummed up lubricant. Based on this, I separated the electric motor from the rest of the assembly. When I applied power to the motor alone, it worked. I'm planning to clean the fan component (the black part in the photo) with isopropyl alcohol and see whether I can make this operational. I will need to find a lubricant for the fan. If that works, I will reinstall the original pump in the car.

[986andmx5]

This thread is very impressive, nice work! If you do end up needing lumbar motor parts send me a pm and I can see what I have around.

[KevinH1990]

Originally Posted by 986andmx5

This thread is very impressive, nice work! If you do end up needing lumbar motor parts send me a pm and I can see what I have around.

Thanks. I have the pump working on the bench and I have an appointment at an upholstery shop on the 18th to have it installed. I plan to test the pump right before I drop it off at the shop. If works on the bench and then doesn't work after it is installed, I will be fairly confident that something other than the pump is causing the problem.

I would like to install the pump myself, but I'm not skilled with upholstery. I can see the pump when I remove the center insert on the seat, but it looks like the bolster needs to come off before the pump can be removed. I decided it was better to pay the shop $100 to install the pump than to risk causing damage that would cost more than $100 to repair.

If you have any 987/997 seat components, I'm looking for the black plastic covers that fit over the front of the seat rails. The 986/996 covers fit on the seat rails, but they don't lock into place on the 997 rails. If you have the 997/987 seat covers, please let me know whether you are willing to sell the and the price.

[KevinH1990]

https://youtube.com/shorts/OEjugR7Zy4E

This video shows the pump running on the bench. When installed in the car, it is in a gray vinyl bag with foam insulation. I expect that is arrangement is designed to reduce the noise associated with the pump's operation.

[KevinH1990]

I don't want to create the impression that I figured this out on my own. A Rennlist user named preppyr6 did the vast majority of the work. Post #73 of this thread https://rennlist.com/forums/997-forum/1279635-18-way-power-seat-test-help-7.html#post19627327 provides details.