There's a recent thread in here where someone posted up pics of their replacement of all the air bladders that are associated with the ortho option. It appears that these bladders start falling apart over time, which of course means they can't hold air and function correctly.

 

Hm. If it is the case that my air bladder(s) is/are leaking, wouldn't I at least hear some sort of hiss?

I guess I just want to rule out all the simpler options before tearing out my driver's seat. :crybaby2:

 

I just looked, but couldn't find any references to ortho in the manual, but give it a try. I know next to nothing about this fairly rare option over here.

 

I am very interested in these rarely seen seats.

My 88 TE#3 (pine green over java leather) has dual ortho seats. My 90 TE 4Matic has a driver's side ortho seat in maroon leather. I grabbed the gray leather ortho seats out of a junkyard 92 300Te 4Matic.

From what I know, cars with the ortho option have a special central locking pump with a port for the seat circuit. There's also an additional wire (bk/y) running from Fuse A/X30 to the pump electrical connector.

The diagram indicates that leather upholstered seats have one fewer air bladders than tex upholstered seats.

It's not clear what activates the pump. I'm guessing that it's a pressure switch in the pump assembly becasue the thumbwheels mounted to the sides of the seat cushions are pneumatic only.

The factory electrical/pneumatic diagram for the system is pretty poor but if you PM your email addy to me I'll send it to you. Then you can figure it out and I'll benefit!

 

My seats are 'partial leather'. The center is textile and the sides are leather.

 

Sure wish I could get my hands on one of those Taxi consoles

 

I need documentation on this topic. Sorry for updating the thread a long time ago.