I hooked up a new trailer brake actuator that required tapping into the cold side of the brake light wiring at the brake pedal switch. It also required a good ground, which I didn't have the first time I tested the actuator. The ground I chose was at the dash, and was not sufficient. The actuator buzzed loudly when the slider was moved and after a couple of other wiring checks I relocated the ground wire to a solid chassis point. The actuator stopped its buzzing, and works properly. Immediately thereafter I noticed my cruise control wouldn't come on. Fuse at the fuse block is fine.
I realize that the poor ground probably resulted in 12 volts possibly being looped into the cold side of the switch, but that shouldn't have been a problem since that is what happens when you step on the brakes (to turn on the brake lights and/or turn off the cruise control).
Anyone analyze this differently, or have any idea of what damage might have been done if any - and where to look first? Thanks