Not sure which wires attach to what on your trailer connectors? This is used in but may also be used in other areas of Europe. The routing is not on the above Trailer Wiring Diagram because it is optional and different for every trailer. Vehicles and trailers with 6V can use the 7-pin or 5-pin connector, but these are rare today. Some also have side markers and running lights. When the taillights and brake lights are used at the same time, it creates the maximum amp load of the lights on the trailer. Note, that this type of 4-pin connector is less common, that 4-pin flat connector. Size: This wire should be at least as big as the largest wire in your harness.
For a single axle, 14 gage is good, but for tandem axles, use 12 gage wire. On older trailers there's sometimes a 5-wire setup using a 7-pin connector. By leaving access to the wire routing, running the additional wire is not so difficult. Tail Light Converters Taillight Converters are used when the tow vehicle has separate wires for turn signals and brake lights 3 wire system. Should I unplug my boat trailer when I back my boat into the water? Other styles exist — though the pin-outs are often different. To determine how to wire up trailer lights, you need to know whether your vehicle has a factory-installed trailer package and whether a plug-and-play T-connector is available for it on the market. The second, which is the most common problem, is a weak ground in the system.
The basic purpose remains the same whether your truck and trailer is using a 4-way, 5-way, 6-way or 7-way connector. Another really good source of information with a trailer wiring diagram comparing different styles of connectors is at You can get most trailer electrical items at any trailer parts store, or online. In this case, you will need a set of wiring taps and a pair of pliers. If a ground problem exists, it will show at this point. Now take the sharp end and pierce one of the wires going into the back of the tail light. Check all wires for bare copper or places where a wire or cable could be pinched.
You should always unplug your boat trailer when backing into the water. A poor ground that is strong enough to provide some lighting functions but not all. For lights, a relatively small wire gage works. The 5-Pin flat connector above is nice for easy handling, but if your vehicle already has a 7-pin, just use it. That said, for specific situations, there are industrial standards with different connectors and wire arrangements.
They supply power to the taillights, turn signals, brake lights, , reverse lights, auxiliary power and include a ground connection. This is accomplished by tapping into the tow vehicle's electrical harness to transfer power to the trailer wiring system. This is done in one of two ways. Now that we have the trailer wiring diagram and some definition for connectors, where do the wires actually go? It was not very common but may exist on some vehicles and can result in an unpleasant surprise. Even if your vehicle is not equipped with a connector, it may have a wiring plug located in the rear.
Some requirements need them, and some do not. The fifth wire blue is meant for reverse lights; this connection is needed to disconnect the hydraulic trailer coupler or actuator when the vehicle is backing up, thus deactivating the brakes on a trailer. The worst that usually happens with screwy trailer wiring is a blown fuse on the tow vehicle—or something wacky, like reversed turn signals or blinking brake lights. However, if you have electric brakes or auxiliary power, this wire must be larger. The difference is that an additional connection for and that battery charging in the trailer is shared with other consumers. You just need access to the wiring. While the flexible sealed conduit nestles in and secures to the frame, it protects the wires from snaggs and from weather.
Get out your regular old and put the clamp end on a good grounding point. In the Trailer Wiring Diagram and Connector Application Chart below, use the first 5 pins, and ignore the rest. This diagram shows the colors of a basic trailer wiring setup as well as what each wire is supposed to be connected to. Some 12 volt batteries produce up to 14 volts on full charge. We also recommend connecting the white wire directly to the trailer frame in addition. While it's never a good idea to dive into a wiring project blind, trailer wiring is actually very simple to.
Yeah, most trailers are never submersed, but almost all get very wet like in heavy rain or when washing. The places to check grounds are as follows. Access our store as a guest! And, so many kinds of trailer wiring connectors. They make these testers for small and large wiring plugs and they really make troubleshooting your trailer wiring much easier! If you think changes might happen later, then leave access to the wires. Depending on the model, the location may vary from inside of trunk to under the rear floor panel. When wiring trailer lights, make sure to route the harness away from anything that could damage the wires.
If you've ever found yourself in a Walmart parking lot, in the dark, in the rain, trying to fix your trailer wiring with flashlights you know how much fun it can be. Typically made from die-cast metal construction, they offer a concealed terminal with a dust cover for protection against the elements. . The trailer wiring diagram shows this wire going to all the lights and brakes. While none of these are things we look forward to when pulling a trailer, they are also easy to correct. For a large enclosed trailer with lots of running lights, consider a larger gage.
If you have a good repair manual, and you should, you can use the wiring diagrams inside to find the correct wire for your trailer wiring. Calculate the amp load your trailer is pulling, see below. By law, trailer lighting must be connected into the tow vehicle's wiring system to provide trailer running lights, turn signals and brake lights. When running wires consider the possibility of changes down the road. Trouble free operation with higher quality lights make them worth it. This is the style we recommend.