Headlights flash when brakes used. Overcome by turning headlights on but then stop light on spoiler sometimes comes on. Cruise control cuts out without touching brakes. recent history was blown brake light.

brake lights operate off a simple switch mounted to the bracket of the brake peddle. that switch can easily have a wire pulled out, the switch it self dies from use. a fuse in the fuse box in the lower part of the could be blow. as far as the cruise going off when headlights are turned on, could be the switch on the column itself is worn out. remember your girl is a teenager now, they give you the most random problems. (girl being the truck)

short circuit in the switches somewhere

The rear spoiler and both rear lights should come on with the car off and brake applied, but no other lights should,The Only lights that should work on any vehicle when it's turned off is The headlights,brake lights,and hazzard light..

Your cruise will not work if the brake lights are on just like the cruise disengages when you hit the brakes.As far as the brake lights with the headlights,sounds like there is something crossed.If you hold your breaklights on with your headlights off is there a glow of the headlights or your running lights.If your rear bulbs are the round push in and turn type make sure they are installes correctly.You may have one where the contact on the bottom of the bulb is causing a jump of power from your running/parking light over to the brake light side.Well hope this helps and good luck.

faulty ignition switch

hi poss one or both brake light bulbs filaments are touching causing a back feed note if the brake lights are on the cruise control is cancelled

You have a short somewhere dude

The cruise control is terminated by the brake lamp circuit, Check the brake, tail lamp for water or a short. Your turn signals are on a different circuit. Check the bulb sockets closely for corrosion. Failing this check connectors for the tail lights for possible water penetration, or loose connections.

Hope this ia of some help
Ed

take it to the work shop

Sounds to me like you may have a instrument cluster problem.