CAS is the Car Access System
I believe the OC3 is the seat mat sensor itself and the SBE is the control unit and I don't think you have either as you have a CAS. I have a 2004. I know mine works as intended. BMW always changes control modules and their functions so you may have something that works different from mine.
FOR ME: IT ILLUMINATES ONLY WHEN NO PASSENGER IS DETECTED.
However, for you it may be different and I'm sure it is because your illumination is different than mine. Also remember reading about someone being able to turn off their airbag with their key for child occupancy. I think it was EU model...never checked mine for this feature.
Good luck

 

Yeah I agree, it sounds like there are at least three systems for this mat. The key/turnoff you refer to I know was on the Z3 & Z4 for for ECE cars. When you open the door it is located on the side of the IP so you can turn off the AB completely. Not sure about the E60 ever having this. It would be interesting to find out when the mats changed as in year model. My friend has a 2007 530 and his behaves identical to mine. What sparked my interest in all of this is the other day I noticed it was on and hadn't noticed it on before. Then I sat in the seat and it remained on which really concerned me. After turning off the car for a few minutes and restarting it seemed to work as normal. Now after the discussion this morning I hear the leather can cause it to do strange things as it contacts the sensors.

 

yes, as far as i know the E60 in the EU has an option to turn of the Airbag with a key. Most other brands here have this standard but on a BMW this offcourse is an option. Likewise for Cupholders .

 

I know the E60 in Eurpope allows you turn on/off aibag. I haven't checked my E60, E46 or E85 to be quite honest. Never even looked at the owner's manuals for any of them! LOL

 

I'm sure you don't. I know the E85 IP has to base substrates. Actually mold difference and not just water jet cuts. The ECE would not come with the knee airbags like the US has. Well, unless you went over to Europe and bought one and then had it sent back here.

 

No i actually have the button. I don't know if it was imported from EU or built here in states but it definitely has the passenger airbag on/off

 

Hey Achtung, I mis-spoke about your E85. I went back through my notes and the airbag switch on the pasenger side of your IP was 100% in US and not required for most other countries. Also, the US will have a knee airbag under the steering column, ECE does not, they only have a knee bolster. So if you have the knee airbag, then you have a US IP.