E39 525it auto - Sports seats too high.

[patrm99]

Hi Everyone - This weekend I swapped my standard seats for sports seats. Initially I found the drivers seat would not go back nearly far enough (i'm 6-2"). After much looking I found the little clip on the toothed rail that restricts max rear movement. I have no idea why BMW would install this clip, but my only clue is that the donor car was a 6-mt and perhaps its clutch related.

My real problem now is that the drivers seat won't go very low - my head is quite close to the roof. Tilting the seat helps a little. Oddly the passenger seat does everything I would want. I have a 2003 540i 6-mt and the comfort seats are very versatile and really everything one might want.

So my question, is there any solution to the high seat issue ( maybe another clip or hack ) or is that just the way they are. Honestly I am considering reverting to my torn standard seat.

Any comments, insights would be much appreciated.

Thanks

Patrm

[SW530]

You might try putting the seat on the bench and connecting 12vdc to the two spade lug connectors and watch what's restricting the seat movement. My sport seats move back enough for someone 6'5" at least and goes low enough so it's like you're almost sitting on the floor.. so there should be a good bit of range on sports seats.

[StephenVA]

I pulled 22 cents out of my tracks before I solved my own seat traveling issues. Bent coins never come out

[crazy4trains]

I'm 6'-5" also and have removed the clip on the rail. My seats have great range of travel and give me plenty of headroom. Do some more diagnostics.

[kallekula]

Sounds weird with that clip. Did you try to just remove it?
Im not sure if its related but my driver sport seat refused to move up or down. I could hear motors working but no movement. In each seat motor there is a mix of gears inside of them, plastic n steel. The plastic ones were ground down. Went to the boneyard got new ones filled gearbox with lithium grease, probably way too much worked fine after that.
Hope that can give you some hints? Im assuming you did all the wires for backward/forward etc.

1DDB2A63-73C6-4EE8-8884-B457A03182EB.jpg
A57C59E8-208D-4DC4-8616-87A6BCB3BFCD.jpg
DC5AEFD5-A5F0-42BB-A946-23A1B82C0279.jpg

[patrm99]

Thanks everyone. I pulled the clip and I get more back movement, but still 2-3” less than the passenger seat.

I plan to follow SW530’s suggestion and put the seat on a bench, power it and see what going on.

Best

[crazy4trains]

Yes the passenger seat will go way back. Just can't recall if mine goes further than the driver side.

[patrm99]

Well, seems my "up/down" motor or mechanism is not working no noise either. I think when the seat goes down all the it also back a bit further. Looks like something similar to kallekula.

Luckily I have a donor ripped seat whose mechanism looks identical. Here we go down the dismantling car seats rabbit hole.

Thanks again !

[kallekula]

Yeah, quickest way is to use the spare seat. Power it on outside too so you know it’s straight. Do all the cables and look inside the gearboxes too. Might be something easy as the seat controller too. Good luckl
EDIT: did you check the comfort/sport compatibility?

[patrm99]

I was able to solve the problem. Before diving into motor / mech replacement I decided to check electronics. Attached to both the up/down and recline motors is a small black box that accepts the power connector.

The box cover for up/down is held by 4 small clips and in there is a small circuit board. Access is easy with the seat out. Mine was corroded due to some liquid incident in the drivers seat in its previous life ! I was able to get the same circuit from my old seat , cut the 2 output wires and solder in the replacement. Now everything works.

Also, when the sports seats go down fully, they also go back a further ~2".

Photos below of the corroded and donor circuit board plus black housing box. The board is inside the black box with the green label. I would imagine this is not an uncommon failure due to liquids and the location of the circuit boards - right beneath the drivers legs. Hopefully this will help someone else.

Thanks for everyones help.

IMG_7571.jpg
IMG_7572.jpg