Swivel Front Seat Won't Adjust

We’ve just had a great first summer in our Sigma, having had 3 weeks in France and a week in Scotland, where our van has performed magnificently and we’re really very pleased with it. 

However usage has highlighted some snags, the main one being the front passenger seat won’t adjust and which my wife finds quite uncomfortable.

I’m wondering if anyone has experienced the same problem and can give advice before I start dismantling blind?
Both the seat height and rake adjustments appear seized.  They are both round wheels on the side of the seat which appear to drive cogs on each side of the seat and linked via toothed belts.  There is slight movement in the belt and cogs which would seem to indicate the jam is somewhere other in the mechanism.  The seat moves forward/back and rotates freely.

Driver’s seat is of similar construction and has full movement.

All advice welcomed.

Thanks
Alan

Hi Alan
When I first had my Sigma 2007 we had the same problem. The Knurled wheels had no noticeable effect. We found that on the front edge of the seat there are two black moulded panels one on each corner  which can be used to adjust rake and height. Fortunately my Nuevo has a more logical system. Hope this helps.
denboy

Well well well, it works! 

Well, partly:  on passenger seat, lifting the left side corner panel allows the seat to recline, however lifting the right side panel permits the seat to rotate.  On driver's side, the left controls rotation and the right controls reclining.

The odd thing is that both adjustment wheels on the drivers seat do work also, controlling height and rake.

So what's the purpose of all the belt driven engineering?  Daft or what?

Many thanks, Denboy!

Hi Alan

Glad to be of some assistance.  I'd forgotten about the swivel tab put it down to old age.By the way even the salesman didn't know of this little trick. Seats were more comfortable on the Sigma than our Nuevo although they are still quite good.
Best regards
Denboy

I'm still curious as to how all the engineering is supposed to work so have fired off an email to Isringhausen (makers) Service Dept.  I'll post any illuminating results.

Cheers

Isringhausen.de replied that they couldn't find my seat serial No on their system (I had same problem on their web site) and asked me to send them photographs.  I sent them photos of the seat, and of the serial no plate on the seat.

They duly replied that it wasn't one of theirs (Germany) but one made by Isringhausen Italy with whom they have no contact.  There is no info whatsoever on Isringhausen.net, the Italian site which appears to be customer log in only.