What type of wiring system is often used in trailers for lighting?

The 7-way connector system is widely used in trailers for lighting because it provides the necessary functions to operate the trailer's lighting and braking systems effectively. This connector configuration typically includes circuits for tail lights, turn signals, brake lights, and ground, along with additional circuits for auxiliary functions like electric brakes and reverse lights.

The versatility of the 7-way system allows for a comprehensive connection that serves various types of trailers, from small utility trailers to larger RVs and fifth-wheel configurations. This makes it suitable for many applications, ensuring compliance with safety standards and functionality across different lighting setups and trailer sizes.

In contrast, the other connector systems mentioned, such as the 4-way, 5-way, and 6-way configurations, might provide fewer functions, making them less ideal for heavier and more complex trailer setups. For example, a 4-way system typically includes only basic lighting functions, which may not be sufficient for trailers that require additional signals or features.