All motor vehicles should have a test switch for all external lights. May be some do, but considering its a requirement to get your drivers licence there should be a feature like this on all vehicles sold new. As its impossible to check your brake lights with out help or a old stick.
Dust in Ute, Manufactures or For wheel drive specialist need to solve this problem. I have had a Ranger, Colorado and even my old Commodore. They all have had the same problem with dust building up under the tonneau cover.
They need to change the aerodynamics to stop causing a vacuum above tonneau cover or build some sort of system to get airflow from the front of the ute to pressurize the tub to stop the tub sucking in dust through the tailgate. The Tubs with a ro...