I know probably everyone with an e34, has currently, in the past, or will in the future encounter the common seat issues the e34's with power seats face. There have been many threads on this but all of them lacked certain details that I feel could have been helpful. I'll post links to those threads I know of, and my insight. If you have any questions or insight of your own, please feel free to add. I know there are a few questions out there that I dont know have been answered. So here it goes.

First off for those of you that have the problem and dont know it, or dont know what the problem is, the power seats on e34's have a tendencey to twist and go un even in their adjustments. Some detailed examples of the common problems are: the back rest twists when reclining or ...Un...reclining... :95 This is due to one side haveing adjustability and the other not. It creats a twist of the backrest. Another common problem is the butt cusion going up and down un evenly. Again this is due to one side moving but the other side not being able to. And the last problem that this particular fix will work for is the head rest. The head rest is pretty streight forward, if its broke it wont move up or down.

So now onto the actual problem you are most likely having. This is something that I have not seen explained, and I think it is helpful in understanding the fix. The seats have motors and 2 cables that run to each motor. These cables are flexable and round with square ends. Basicaly they work like a flexable extender for a ratchet and socket. One square end goes into the motor and it links the motor to (this part im really not sure on as I didn't trace the problem this far) what ever actualy moves the seat. The problem occurs when the black plastic shroud around the cable streches. This prevents the end of the cable from entering the motor. If the cable is not in the motor, the linkage is broke and the motor will spin, but the cable that attaches to what ever makes the seat move will not.

Another bit of info that smarter people then I may have picked up on but I did not. There are 2 cables for each motor, one is for one side of the seat, and the other is for the other side. So if when you recline the seat, the right side moves and the left side doesnt, the left cable needs to be fixed.

Also the 2 main motors reside under the butt cusion. The one closest to the back of the seat opperates the recline feature, and the one closest to the front of the seat opperates the up and down feature. The motor for the head rest is in the backrest of the seat. The second tutorial mentions this but I didnt find that till half way thru.

So I think that is all clairification I found in doing this. It took me probably over an hour to figure this whole thing out the first time. (I need to go back tomarow to finish everythying up) Hopefully this thread will help you take less time to fix your seat.

Here are the two links to DIY on how to fix it. If for some reason these ever die let me know and I'll post my own write up.

http://bellsouthpwp.net/m/i/miales/seatcablesfix.htm

http://www.nmia.com/~dgnrg/page_11.htm

Some info that hasnt been covered to my knowledge are how to fix the seat part of memory seats. I saw someone asking this in another thread. And I have adjustable thigh supports. One doesnt work and they dont appear to be the same as the other features. Anyone know how to fix these things?

Oh also, when you are loosening the bolts on the motors, make the seat go all the way up so you have room to move a wrench. I wasted alot of time trying to loosen them and felt like an idiot when i realized how much easier it could have been.

Great thread here, I have the seat problems with both my front seats. Will be trying to fix them next week for sure.

Its really not that hard once you know how to do it. I clipped not enough so my back rest started twisting again. Today hopefully I'll get it down. Better to do to little then to much though. You can always clip more, but its a pain in the butt to add.

this one should probably be stickied for all the people who have to deal with this issue.

I still have the issue on my memory seats, and it doesn't relate to the cable fix.

edit - Could be this http://www.nmia.com/~dgnrg/page_32.htm

I guess I was lucky, mine did the seat twist thing. One day I leaned the seat down all the way back when suddenly I heard a fairly loud click and when I brought it back up again, no more seat twisting. :redspot

Ok I got rid of the seat twist, and fixed both my head rests. My un even up and down on the driver seat still hasnt been fixed yet. Its kinda confusing. From what I can tell, one side of the motor is for the front of the seat and the other is for the back. If this is the case, what is causing mine to go un even left to right? My problem is when I live the back part of the seat up. Also dont know about the thigh support yet.

I started this thread in hopes it might get stickied seeing as its a common problem. Maybe one of the mods can sticky it.

my seat just rocks slightly at acceleration and when stopping not too bad, but noticable when you pay attention to it.

Isn't there a fix for this too?

my seat just rocks slightly at acceleration and when stopping not too bad, but noticable when you pay attention to it.

Isn't there a fix for this too?

There is but can't remember the site it is on. I'll post a link if I can find it.

Ok, found it, http://bellsouthpwp.net/m/i/miales/rockingseatfix.htm

Luckily I have never had this problem with any E34's I have owned...I will remember this so if it happens in the future I will know how to fix it...Thanks for the tip! :)

I bought my 95 540 for a great price due to the seat being stuck down and twisted. It made for a suckin' 1hr ride home. I got it home and took it appart, made some cable adjustments, and voila! The car now has over 185K and next will be the thrust arms with HD bushings.

I bought my 95 540 for a great price due to the seat being stuck down and twisted. It made for a suckin' 1hr ride home. I got it home and took it appart, made some cable adjustments, and voila! The car now has over 185K and next will be the thrust arms with HD bushings.


Got a nice set of thrust arms here for cheap, if you want

Damn! I just picked up a pair off e-bay for $95 + shipping. They are Lemforder with 750 bushings.
Is that a good deal?

Thanks for the offer, I came over from another forum that sucked, this one is great!

The passenger seat in my 92 525i suffers from the right back arm being stuck in the fully reclined position. Is this most likely the same problem?

The passenger seat in my 92 525i suffers from the right back arm being stuck in the fully reclined position. Is this most likely the same problem?
Sure is. This would be the seat back twist problem. When you try to bring your seat back up, one side goes and the other stays resulting in a twist.

Today I removed my passenger's seat to check the drive cables going to the backrest motor. Both tips are extending the proper length (1/2") from the shaft. What's happening is that one side is stuck - if I depress the switch, there is a very loud grinding noise coming from the gearbox. I'd like to open it up and see what's going on, but I've run out of daylight and had to reinstall the seat.

How do I take out the gearbox? Is it possible for me to manually adjust the backrest without removing the gearbox?

Awesome thread.

I have always used the method of cutting the sheath a few inches away from the motor, then cutting out the 1/4" section, then sticking them back together, wrap fuel line around it with some clamps to hold it together. This is the method I first learned, and to me it might be easier than having to heat the metal collar, remove the sheath, then going back with it.

Instructions in other languages

German
http://www.pagaduan.org/bmwe32/Fahrersitz.htm

Japanese
http://infinitier.ddo.jp/e32/page/mainte/mainte_047.htm