I have a weird issue with my 2013 991 C4S 18-Way Sports Seat Plus. Starting a week ago, the drivers seat lumbar adjusts itself while I drive. It's sporadic and I originally thought I was my back having spasms. Then I pressed my memory and felt the lumbar retract / deflate. As I continued driving down the road I felt it start inflating itself again. Now this happens almost every time I drive the car and the lumbar is fully inflated by the time I get to work. Occasionally the bolsters move themselves as well. I have reset the memory of both keys, disabled auto memory and comfort access. Essentially nothing has really worked.
I had it in the dealer today and they could not replicate the issue, but on my way home it happened within 5 mins. Turned right around and nothing happened again for them. Essentially the dealer told me if it keeps happening to make another appointment. They will have someone drive it home and back to dealer for extended test drive for more testing. Before I go nuts, has anyone else had this issue and know whats wrong?
On a side note, I noticed this started happening the same time I got my iPhone 7 Plus and hooked it up to my car. Now while I am 99% sure this should have nothing to do with it, I turned off my iPhone 7 Plus and took another drive. Nothing! This could be a coincidence, but will have to drive it more tomorrow with my iPhone off to confirm if it's related.
Update: I drove around a significant amount today leaving my iPhone off and the seats did not move at all. I will continue to drive around tomorrow leaving my phone on to see if the issue comes back.
Is it possible the wiring is acting as an antenna and picking up signals my iPhone is giving off? I am baffled!
I think you have a short in the seat controls. Although if your phone has the ability to control it, maybe someone should make a seat adjustment app.
Update: No dice... Seat started acting up again with iPhone being off. I will be contacting my dealer again stating issue is still there. I will mention that it sounds like it could be a short in the seat controls.
I'm curious to hear what they find. There's so much software in cars these days, it's hard to guess what it could be.
My car goes back in next Thursday so I will update on what they find out. My guess is either my weight pressing on the left bolsters is compressing something to make connections in the switches, or the module that controls the seat has a short. It's not just the lumbar that has moved now. Functions of the seat such as side bolsters, bottom bolsters, and back of seat are also affected. They are also the top most controls on the seat which is why I have a theory about my weight pressing down and completing a circuit. It also seems to be a lot more sporadic when listening to audio with enough bass that shakes the car.
