How do you check your brake lights? Does the car tell you?
Unfortunately my vehicle isn't clever enough for that, but I park under a carport that has a solid rear wall - you can tell if the lights are working pretty easily looking in the mirror when they are applied. For checking a trailer lights before towing, I have a screwdriver that lives in the vehicle which is the perfect length to rest between the driver's seat mount and brake pedal to apply enough pressure to activate the lights. Easy one person job.