Fitting electric memory seats to a car with manual seats as standard

Hi all, I've been googling and reading for 2 days now and still haven't been able to sort this, I'm hoping it is possible and someone who has done it can help. I have a 2007 Cayman 987.1 with manual seats. Manual height adjustment and back and forth adjustment. The recline is electric. I have purchased a paid of sport seats from a 997.1 , they are 18 way, heated and have the memory module under the drivers seat. My current car doesn't have heated seats, but not fussed about getting that working. I swapped the passengers and that was plug and play, all electrics work. Fantastic. I swapped the drivers seat and nothing. No live is the seat at all. I expect this is due to the memory module not being connected. I don't care about the memory option, and I don't have the buttons on the door anyway, and don't plan to try and get this working. I would like to get the electrics to move the seat working, like the passenger. I inspected the main seat plug and see the power/negative are in different locations in the plug . So I de-pinned it and swapped it round. Still nothing.(Apart from the heater started to work) Has anyone managed to fit seats like these and get the electric working? I have tried putting12v to the seat and get nothing, I can power the motors direct but the switches go through the memory module. Any help is appreciated. Thanks, Simon

"switches go through the memory module"... if that's the case, then there is your problem. My guess is that without the memory module, there is no "controller" available to handle the motors. For that matter, the switches may just be command signals to the memory module, which actually handles the movement... which, again, is why nothing works? Again, I'm just guessing, as I don't have a schematic nor do I know how they system operates normally... You seem to be good with wiring, so I would check to see where the wires from the switches actually go. Do they go to the motors directly (tha'ts probably what's happening on the passenger seat, which is why it's working)... or do they go elsewhere. If they go elsewhere, then that explains the issue. Assuming the above is true, if you're more adventurous, you could (potentially) rewire those switches to control the motors directly... and get the passenger-seat-style operation you seek. You will need to check the switch current limits or use relays, etc... again, stuff an electrically savvy person could handle (I am happy to help remotely) but it's not plug and play. For that matter, I wonder if you can get the memory module (skip the switches) and get it working that way? Again, I don't know the system well enough to know if any of this will work... just throwing out ideas.

I did the opposite on my now departed 987 and installed sports seats on a memory car. To make the seats work I needed to de-pin the power from the memory module and attach to the standard seat connector. I have an old thread on this either here or on RN if you’re interested.

This is an interesting quest since I've been tempted a few times to try this myself, but the cost of even used power seats put me off it. I came >< - this close to tossing myself into the fray this morning. At a local PCA club fleamarket, a chap had a set of 987/997 full power seats for sale - $100 for the pair, and they looked almost perfect, except for one thing.. they were gray and my interior is blue. Thank Dog they were the wrong color, it kept me from going down this path. BTW - @schwinn is undoubtedly correct. Without the memory module the driver's seat isn't working (and it's the only seat that has memory on it.) The memory function works by having a potentiometer attached to each seat movement, so there is a resistance that changes with movement. That resistance is measured and memorized by the control module when you store the settings, and then when the memory recall function comes into play - the module moves the motor for that function until the resistance measured on that movement's motor matches what it has in memory. There really isn't any other way to do this. That means the power to the motors is provided by the module, not the switches - they just talk to the module. Could it be done directly? I imagine it can be if you can find a module like the one used on the passenger's seat and duplicate the wiring. Not a trivial exercise which is why I'm glad I'm not chasing this one, I've done enough of these sorts of things to know it always sounds easier than it is. BTW-II - just took a look at AllDataDIY diagrams for the "comfort" seats (which have things like an air-pumped lumbar support) - and the diagrams are more complex than the entire wiring diagram for some cars I've owned. And this was without a memory function. Good luck!

Hi, thanks for your input. I do have the module that goes under the drivers seat (right had drive car). If I was to put power to the module, would you expect the motors/switches to work? there isn’t a module under the passenger seat, that just plug in and worked. Looking at the seat the power feed goes to the switche’s, now a secondary modules like the drivers memory one.

This is an interesting thread. Please post back if you get it working! I have the power/memory/heated in my car, but always fun to see how people get their projects working. Could you source the buttons and related electronics from junkyard? You wouldn't have to mount the button in the door, but stuffing the electronic under the seat might get you up and running.

For anyone following this, I have now for a fully operational 18 way adjustable drivers seat as well the passenger. My issue was fitting a seat with memory into a car without memory. The passengers was plug and play, the drivers not... In the end I purchased a wiring harness from Latvia for a 18 way seat, without memory, and a switch unit (these are different too) from the US. After swapping these over it works perfectly. An expansive job, from Porsche these two parts are over £1000. I managed to get them both used for £500. I think I was very lucky to find these parts separated from the seat. I doubt I would manage to do the same again.

Hi Synthedup, I am in the same position, only with both driver and passenger seats! Can you share the list of items that you had to swap to get these to work? It looks like I'm going down that same path. Interestingly, mine both seem to have the same module under both seats, so they must code it to work on the left or right side??

Hello, It's strange that both your seats have the memory box, from my research I only found this was ever an option on the drivers seat. Happy to be corrected if that's not the case. I wonder if someone has purchased a set of US seats, and a seat of EU seats and used both passenger seats to make a pair that are plug and play. To get your seats working isn't going to be cheap. You need a switch unit from a non memory seat for both. I believe the part numbers are as follows. These are about $650 each. right seat - 99761371801 Left seat - 99761372102 You will then need the wiring harnesses from a non memory seat. I don't have the part number but Porsche should be able to help. These are about $150 each. I didn't replace the harness in the back on the seat, but instead I chipped the memory loon and soldered this to the new loom. The wires and all colour matched so was an easy job. You might want to reach out to dC Automotive they have loads of used parts and I expect may have what you need.

Thanks Synthedup for the info, The seats that I have are later '14 981 18-ways sport. In those years they must have extended the memory seat option to the passenger side as well. Both seats have the same module down to the part number, so they must be coded to the location. I am thinking that the reason that mine don't work is the same reason that yours didn't work, even though the model and part numbers involved are different. What I'm trying to figure out now is if there is even an 18-way seat without memory to swap parts from... I'm not sure that there are with the 18-way, or they are probably like hen's teeth. To make things more interesting, some have reported that you only need power and ground to get these seats to operate, but that has not been the case for me. I am wonder if theirs were non-memory, and the ones that I have are memory. The outside of the seats look identical. I am waiting confirmation from the person who posted the pics. The other thing is that my seats were in an accident. The seat bag on the Passenger side blew. That's no issue to me as my 996 has no seat bags, so I can't hook them up if I wanted to. BUT I'm wondering if there is some accident lockdown mode that has to be cleared on my seats before they will move again. Any ideas?

Quick question for those who retrofitted the Memory seats. I have the bucket seats and want to add the memory seat module to get the mirror tilt in reverse. Is it possible to just buy the module and program the feature with PWIS or do I need to buy the windows switch as well?

I'm also in the same boat, having acquired a set of adaptive sport seats from a 997.1 Turbo to put into my 987.1 BS, which came with the standard non-power, non-memory comfort seats. My Cayman has the manual sport seats and I much prefer the side bolstering to that of the comfort seats. Anyhow, the seats I acquired came from a car with memory, and the driver's seat has the memory module installed along with it, so I'm looking to figure out what that memory module needs to allow for the seat adjustment switches to work. I'm not looking to get any memory functionality, only to get the seat working like a non-memory power seat. I've found a pinout for the input of the memory module, so I can figure out where to feed it 12V+ and ground, and even CAN high/low if needed. I'm not adverse to running wires or fabbing harnesses, or even coding modules if necessary. However, my fear is that the memory module is specifically looking for communication with a memory door switch, memory-supported mirrors, etc. @Synthedup - what did you try with the memory module that failed and sent you down the path of replacing the switches and harness? Additionally, if it needs CAN high/low connected, does anyone know if the terminator resistors are built into the module or if that's part of the harness? The only Porsche I have with memory seats is my 958 and I'm sure those are totally different.

The mirror tilt and other features are in the Front Door L/R modules which you have. There are some setting for Memory Seats in those two modules. The coding part is not the challenge. You have to try your harness and figure out if you need to modify it. I have seen some members swapping Manual to Memory seats from the same platform without modifying their harness. Good luck

Unfortunately, the car doesn't have the black harness that goes into the memory module, so will need to run some wires on my own. That's why I'm trying to figure out which leads the module must have in order to work at all. Obviously it will need power/ground, but wondering if it needs CAN and, if so, what programming this and other modules need to make it happy, which I should be able to do with my Durametric Pro. My CAN knowledge is limited, sadly, so don't really know how the modules communicate, if there are startup messages broadcast, etc. Nobody has confirmed that "just give the module power" works, so I'm guessing there's more. I found this in my search, and those top 13 pins correspond to the input on the memory module. #1 and #2 power and ground I can pull from the existing harness (pins #4 and #9, respectively, on the factory connector). #3 I can pull from the fuse panel, and that should complete the power source to the module. CAN high and low (#13 and #8) I can pull from the OBDII port, and that #9 ground is the shared body ground under the seat, so that's easy. But I don't know what the other pins on the memory module do, or if they're required. I also don't know if the comfort and sport memory module are different on the input side (I would be very surprised if they were), but again, any unknowns increase the complexity of the problem solve.

An update for anyone who finds this later and attempts to go down the same rabbit hole... Unfortunately, I'm still unable to get these working with the memory module. I made some harnesses to plug into the seat memory module; one to pull the big power/ground leads from the existing car-side harness, and another to pull Comfort CAN hi/low and 12V+ from the rear control module under the drivers seat (and a wire for pin 9 to ground under the seat). I recoded the central gateway to tell it the seat memory module was present, but apparently that's not enough to make the system happy. Seat still doesn't move, and Durametric is unable to connect to the seat memory module, so apparently there's still more required to get it up on the system than just connecting the CAN wires.

Afternoon I'm trying to do the same thing and just stumbled on this thread. Do you have a link or details of the harness you purchased please?

I went through something similar with my car, trying to upgrade to better seats. It's a bit tricky, but here's what I learned. Like you, my car didn't have electric seats to start with, and I wanted to add them. I found out the hard way that the memory feature on the driver's seat needs its own box to work properly. Without it, the seat just won't move. I work in a company by driving a Kenworth electric truck , as well, and the experience is pretty similar. For the passenger seat, it was super easy, just plug it in and everything worked. But the driver's seat was a headache. At first, nothing worked. Then, I played around with the wiring, kind of like what you did. I didn't care about the memory part either; I just wanted the seat to move. I ended up taking it to a friend who knows more about car wiring than I do. We figured out that the memory box was the problem because it controls the movements. Without the right setup, the seat is just dead. We bypassed the memory stuff and made the seat work, but it took some time and a lot of patience. My advice? If you're not too worried about the memory function, maybe find someone who can help you rewire it to skip the memory module. It's a bit of work, but if you can get the electric adjustments to work, it's worth it. Good luck, and don't give up. It feels great once you get it all working!