So, you’ve got your trailer connected to your truck with the right hitch, ball mount and trailer ball. You’re ready to go, but what about your trailer lights? If the trailer connector doesn’t match the one on your tow vehicle, or if the vehicle doesn’t even have a plug, stick around. From basic lights to the fridge on a camper, all trailers need electric power supplied by your vehicle, and we have everything needed to make a hassle-free connection.

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There are a number of standardized trailer connectors, such as 4-pin flat/round, 5-pin flat, 6-pin square/round, and 7-pin round. The simplest 4-pin system is used for small trailers, and has one ground pin, one pin each for left and right turn signals, and one for the running lights. 5-pin flat connectors add a wire for the back-up lights. If the trailer is equipped with surge brakes, this circuit also disengages the brakes when the vehicle is backing up.

6-pin square connectors are generally found on RVs to make a 12-volt circuit available from the tow vehicle to run accessories or charge a battery. 6-pin round connectors are common on horse trailers. If the trailer has electric brakes, the 6th circuit is used to actuate them. 7-pin connectors are most commonly found on new vehicles that are prewired for towing. In this case, the 7th circuit is used to run the back-up lights. Fortunately, no matter what connector you have on your trailer, we have the wiring harnesses that will let you plug into your vehicle’s electrical system.

Before going further, the first thing you have to determine is whether your vehicle has a factory installed trailer towing package. If it does, you’ll find an electrical connector at the rear of the vehicle, usually on or near the bumper. If the shape and number of pins (wires) on the vehicle connector matches the one on your trailer, then all you’ll need is a wiring harness of sufficient length with the same connector at each end. If not, we can supply you with a plug-and-play adapter harness that will make the connection. All your trailer electrical functions will work, without any need for cutting and splicing.

But don’t worry if your vehicle isn’t already set up for towing, we can still get you connected without much hassle. For most vehicles we offer a plug-and-play T-shaped harness (so called because it connects to both of your tail lights) that connects your vehicle lights to the trailer lights. If you have an obscure vehicle for which no T-shaped harness is available, we can still help, but some splicing will be necessary. And if your vehicle uses separate bulbs for the brake lights and turn signals but your trailer uses one bulb for both, we can supply you with a converter harness that will make the connection simple.

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