What causes trailer lights to dim?
What causes trailer lights to dim? Most often the root cause for issues with trailer lighting is a weak ground. Strange as it may sound, a loose or rusty/corroded ground can cause a vehicle's trailer wiring harness to badly misbehave and shut down some functions. How do you fix foggy tail lights? Removing Moisture with a Hair Dryer. Try warming the outside of the light with a hair dryer. You can usually get rid of condensation without taking apart your tail light. Hold your hair dryer about 6 inches (15 cm) away from your tail light and turn it on...