Power Seat doesn't go back all the way

[jpm71]

I have a 2003 S430 and the passenger power seat has stopped going back all the way. The button works to move it forward, and then moves it back but stops less than half way back. I've tried running it all the way forward and holding, and all the way back and holding the button to see if it might reset. I also pulled the fuse and tried holding the "m" button and using the control in the opposite direction. Is there something else that might need to be reset to clear out a false stopping point? Could it be the door control module even though the switch seems to work?

[TheBenZo]

Might be a hall position sensor? There is a cable under the seat that unwinds as it moves back. Does the bun work ok back and forth?

[jpm71]

Originally Posted by TheBenZo

Might be a hall position sensor? There is a cable under the seat that unwinds as it moves back. Does the bun work ok back and forth?

Assuming bun is the bottom portion of the seat, that works fine all the way back and forth. It's just getting the whole unit to go back. I took a look under the seat, which I hadn't done yet, and there is a cable that comes out of the carpet, on the door side of the seat, sort of bicycle cable style, and it has slack in it. If that is part of the hall position sensor you mentioned and it is supposed to be taught to keep a measurement of where the seat is, then this is almost certainly the problem.

Any additional input on this cable is appreciated. Didn't look like an easy fix to track down this cable and replace it considering it disappears under the carpet.

[mvmiller]

Does it move back with a memory button? Try one of the presets to see if will move past the half way point.

[jpm71]

Originally Posted by mvmiller

Does it move back with a memory button? Try one of the presets to see if will move past the half way point.

Tried all the memory buttons and it won't get past the same point it stops at with the regular button.

[TheBenZo]

Originally Posted by jpm71

Didn't look like an easy fix to track down this cable and replace it considering it disappears under the carpet.

Ahh its not too bad. Just unbolt the seat and unplug it. But scan it with STAR first, and do a few actuations with the seat to see if it will move past the point it stops at.

[Skylaw]

Try the procedure at post 14, http://www.benzworld.org/forums/w220...st2216730.html. If that won't work, look for blockage in the seat tracks. If nothing there, have it serviced.

[jpm71]

After Benzo's post, I looked under both seats. Here is a picture of the cable that seems to be broken. If you look at the gold screw on the left, you can sort of see the cable that runs to the front. This is the driver side and still attached properly. The passenger side had slack in it as though the cable had broken internally or come detatched at the other end. So my guess is the seat moves forward, the sensor at the other end can't detect that because the cable didn't retract properly, and now it thinks the seat is all the way back.

I appreciate all the help. If anyone can verify this is my problem, and tell me what the part is called, I can do some more searching to figure out if it's diy or a shop fix.

[TheBenZo]

Totally DIY. Its just going to take a little time. The only issue I think you might have is normalizing. But to do that you hold the seat position switch forward for 3 sec after it maxes out forward. Then do the same in back position.

Worse comes to worse, you can take it to a INDE shop that has STAR and get them to renormalize it for you.

Go to www.startekinfo.com and sign up for EPC. Its free. Find your part. Then start calling random dealers to get prices. I usually use Benz dealerships that are kind of podunk (Nebraska, South Dakota etc) because they are cheaper then the big city ones like MB of Seattle.

Glad we could help!