Now, I rarely work on Brake controllers. WE have a tech that specializes in them. BUT, from my understanding of how they operate, just pushing the Brake Pedal will NOT activate the voltage. The Brake Controllers have a weighted or electronic INERTIA control inside the controller. So, when you apply the brake pedal and the Truck/RV starts to slow down and there is that INERTIA, THEN the required DC voltage is sent from the truck to the RV brakes. Just sitting still and pushing the brake pedal may not activate the DC signal. That is why they have the LEVERS or SLIDE button on the Brake control. That is how you activate when not moving. They will also activate when moving, without hitting the Brake Pedal. Doug