76 280c power windows no power
 

This Mercedes 280c 114073 chassis. Theres no power at small fusebox . ( cleaned everything inc the screws) new fuses . and still no power. The window system is wired in reverse polarity with motors. HOW DO YOU TEST THIS COMPLICATED SYSTEM ??

Check out this thread on my windows.
Window fuses located on passenger's side by firewall but I guess you already know that.

http://www.peachparts.com/shopforum/vintage-mercedes/392059-76-280c-fr-pass-window-will-not-go-up-rear-drivers-will-not-go-down.html