'93 190e 2.6 vacuum circuit diagram
 

I have searched threads about heater issues but have not found a vacuum circuit diagram or a component location chart/list. I would really appreciate any help in this direction. Oh, my issue is heater on full through the defrost no matter what.

Thanks for any help.

201 service disc?

Where do I find "service disc?" I have a Haynes manual but it is really sketchy- almost useless. I did an internet search but couldn't find anything referenced that way.

Thanks again