In my case switch 1 was defective but switch 2 was working properly. I was getting intermittent cruise control problems and the etc light would illuminate and I would lose power until I let up on the accelerator, then all would be good. My cousin has a pro model scanner that monitors and logs all available data and it showed a pending code(didn't write down the code #) saying incompatible brake-accelerator position(or something close to that wording). We also noted that brake switch 2 was opening and closing properly but switch 1 remained closed unless you pumped the brakes until it opened which explained the intermittent cruise control problem.

 

I am having the same problem with my 04 3500 Deisel. Have you worked it out yet on yours?