If your brake lights are always on, or your cruise control does not want to engage, once of these little plastic clips may be at fault for the issue. They go into little holes on the clutch (for manual vehicles) or brake pedals, in order to press a switch which tells your truck when those pedals are depressed or not. If the plastic part brakes and falls out, the switch just goes through the hole in the pedal, and the system malfunctions since it thinks the pedal has never returned to the home position.
