I posted this on the other site, cross-posting here as this seems to be a relatively common issue. So I think I figured out why my lumbar support wasn't working right
Issue
:
Lumbar support has a mind of its own. If I saved seat memory with the lumbar deflated after a few drives it would end up fully inflated and I'd have to manually deflate it
Workaround
:
Memory location #1 is tied to the key, and when you unlock the car with key #1 it adjusts the seat. What was happening was every time I unlocked the car it would partially inflate the lumbar support. I "fixed" it by clearing memory location #1, leaving it empty, and saving my preference in location #3
Investigation
:
The lumbar support consists of two air bladders. Bladder fullness is detected by a sensor under the seat. There's a string that runs through a hole in the middle of each bladder with a black plastic disc at the end. When the bladder inflates it pushes the disc forward, this pulls the string out of the sensor and the amount of string pulled tells the sensor how inflated the bladder is.
What I found is that for the lower bladder there was slack in the string when the bladder was fully deflated: the disc was not being firmly held against the bladder. So what I think was happening is that the sensor was getting an incorrect signal and would inflate the bladder until the string had tension on it: the minimum fill level was not when the bladder was empty, it was when the bladder was full enough to put tension on the string
Fix:
Remove the rear center seat pad. You need to lift the pad at the top center to lift it out of a tab in the seatback and then there are two plastic tabs on each side of the pad you need to pop out. Then flop it forward, it's pretty easy
Option 1: (easier, may not work as well) Stick a spacer of some sort around the string under the plastic disk. Like basically make the disc thicker to take up any slack
Option 2: (pain in the butt but this is what I did) The string goes through the center of the disk, wraps around the outside of the disk in a groove, and then is wrapped/knotted through two holes at the perimeter of the disk. It's pretty obvious how it works when you look at it. I pulled the disk as far away from the bladder as I could and then put a clamp on the base of the string to hold it extended so I could work. I then used tweezers to painstakingly undo the string from the disk. I pulled the string about 1cm farther through the center of the disk to take up the slack and then re-tied it to the disk. Then I put everything together and re-saved the seat memory
No guarantees but it seems to be working better and that slack definitely seems like it could cause problems. I can't tell you if the slack is from wear or what, like it's possible the sensor is going bad and this'll just happen again.
This is on my to-do list... But I haven't found anyone showing how to actually remove the seat centers and I'm afraid of breaking something there.
Any pics or tips on removing the seat center panels?
Seat back center is really easy. If I'm remembering correctly, start at the bottom and pull that out. Then work your way up some sides: there are some clips on the side where I just squeezed the sides inwards to release them. At the top is a hook that goes down into the seat frame, just lift the padding up and out.
This video is from a
981
but it looks the same, see about a minute in. He uses a putty knife for the side clips which probably works better than the way I did it.
Excellent, I see it now. He starts with the seat out of the car and top disassembled, but then further in shows the putty knife part and I assume you can start at that middle part undoing the clips, and then unclip the top, and lay the centers down onto the seat bottoms.
Thanks!
