[beyonce]

I have a M235i, and the passenger seat moves on it's own every so often, only happens when someone is sitting in the seat and often happens when I accelerate/go over bumps.

Very odd, anyone have any suggestions?

[overcoil]

Does it just move forward and back ?
( not; up down, tilt or bolster )

If so, press on the seat back near where a shoulder would hit where the switch is for seat forward / for rear seat access.

[beyonce]

Yes it only moves forward and back. Just simply press on the shoulder part? A bit confused on what I should do exactly.

[overcoil]

on the upper side of the seat facing you when you open the door you'll see (or should see ) a black toggle switch that moves the seat forward to aid egress

The ideas is to apply pressure on the upholstery in that area at or around the same level as the toggle to find a faulty wire or connection.

Also. do the same thing on the seat bottom upholstery near the bottom seat switches.

Test if applying pressure to these different areas can move the seat.

[beyonce]

Thanks for the tip. Seems like it moves when there is pressure on the bottom portion of the seat. Would that mean I would have to replace some sort of pressure sensor on the seat? Not sure if this is something I can DIY or not?

[overcoil]

Originally Posted by sam235i

Thanks for the tip. Seems like it moves when there is pressure on the bottom portion of the seat. Would that mean I would have to replace some sort of pressure sensor on the seat? Not sure if this is something I can DIY or not?

it could be as simple as wire insulation that wore of or a bad switch.

Gently press the switch button inwards to make sure it's seated properly.

I'm not good with an ohm meter or testing continuity. Might be best to go to a pro tech.

Before you do anything, use a mirror and a light and look under the seat to see if any connections are obviously askew

[SmellyGreek]

My driver's seat had a 'phantom' movement problem that included the bolster bladder inflating and deflating randomly. The dealer finally discovered it was the control module and replaced it.

[beyonce]

Ahhh I think it's the control module like you mentioned because now the tilt motor is being possessed! lol.

How much did the repair cost you if you dont mind me asking? Debating whether I should bring it into BMW (not covered by warranty anymore) or just replace the part myself. Thanks for your help

[SmellyGreek]

Originally Posted by sam235i

Ahhh I think it's the control module like you mentioned because now the tilt motor is being possessed! lol.

How much did the repair cost you if you dont mind me asking? Debating whether I should bring it into BMW (not covered by warranty anymore) or just replace the part myself. Thanks for your help

It was under warranty, so free. Fault was 8029BE, Part replaced was 61319359835. Hope that helps.