Trailer light wiring may be easy or tricky, depending on what you have and how often you are going to tow. But whether you own a fully equipped tow-ready truck with a factory trailer package, like some of the latest Chevy Silverado or GMC Sierra, or a vehicle which doesn’t even have a plug and which you are going to use for one-day towing, the modern market offers everything needed for a trouble-free hook up.
There are all kinds of wiring kits / connectors / trailer light adapters that make this connection possible. If your tow vehicle and trailer are wired with different sockets and plugs, there is a wide range of adapters that allow for a quick and easy conversion, making your trailer’s existing wiring compatible with your vehicle’s connector. Your vehicle has a 7-pin connector while your trailer features a 4-pin flat? No worries, a 7 to 4 pin adapter will make a conversion.
So, standardized trailer connectors have 4 to 7 pins:
- 4-way connectors (flat/round) are the basic type for small trailers, having one pin for the ground wire and three pins that carry the voltages for three main lighting functions: left and right turn signals, running lights, and brake lights.
- 5-way systems are typically used for trailers equipped with surge / hydraulic brakes. They have an extra wire hooked up into the backup lights.
- 6-pin connectors (square/round) add two terminals, for electric brakes and 12 volt source.
- 7-pin connectors (typically with round or RV blade-style pins) have one additional pole than 6-pin, allowing for one extra 12 volt “hot” lead or backup lights.
There are also multi-tow trailer light adapters that will come in handy if you have several trailers with different wiring connectors. They eliminate the need to buy several adapters, allowing you to mate trailers with different plugs to the same vehicle socket. Whether you need a 7 to 4 pin adapter with integrated test lamps, the right adapter which will establish a connection if your tow vehicle has the socket on the left and your trailer has the plug on the right, or the one with a backup alarm, you’ll be able to find just the right option.
So no matter what it is that you have, be it a late model Jeep, an Audi with multiple tail lights, or an old Nissan that seems to be an indestructible workhorse, the market has you covered, offering a number of solutions for safe towing.