Does the cruise control light come on when you turn it on? If not it may not be getting power.
The brake light is on? Is these the emergency brake light, if so this light comes on when the emergency brake handle is pulled up or the brake fluid is low, or the brake fluid switch on the lid is not working.
There is also a brake light out indicator on the dash. This light comes on if a brake or taillight is burned out.
The cruise is a rectangle box in back of the radiator drivers side. It has a cable running to the throttle pulley and plugs into the cars wiring. Just replacing the brake lines should not cause issues.