how do i adjust the rear brakes on my fiat ducato motorhome?

Three things
I assume they are drum brakes
take off road wheel and rotate brake drum to locate inspection hole and then adjust knurled nut with a screwdriver flicking it around.
Have you checked out the load balancer - front to back breaking which is adjusted on a small arm near the back of the camper. I was told that with the engine running and the brakes depressed the solinoid at the rear can be felt to vibrate.

John
August 2010