When Did 7-Way Connectors Start Using the Center Pin for Reverse Lights Instead of 12 Volt Power

Question:

When did the center pin change from 12v power to useless backup light that NO trailer has. ???

asked by: Nick

Expert Reply:

The center pin on a 7-Way connector can be 12 volt auxiliary power or reverse lights. If you are installing a 7-Way such as # PK12703 then that center pin can be wired to be anything you want. In fact, any of the pins can be whatever you want provided they match what the trailer requires.

As far as when factory wired 7-Ways start using the center pin for reverse lights I couldn't tell you but it has been that way for as long as I can remember. Also there are other types of 7-Ways. A semi 7-Way has different functions than an RV 7-Way. And a 7-Way with round pins does use the center pin as 12 volt power.

expert reply by: Michael H