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Curt Wiring - Wiring Adapters - C57674 Review

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Review of Curt Wiring C57674


Today we're going to be reviewing part number C57674. This is the Curt Wiring Adapter from a 4 way flat to both a 7 way round and a 4 way flat. The multi function vehicle end connectors are going to convert any 4 way flat end connector vehicle plug to a combination of a 7 way outlet, and that's also going to have the 4 pole flat outlet as well. It's going to include the integrated test lamp. You can see that it's going to have the display right here which is going to display the proper connections. This is going to indicate and show if the wiring on your trailer isn't working properly.

It's going to show whether you have burned out bulbs, poor connections, things that go along with that. It's also going to include your mounting bracket and all the hardware that you need to get the socket mounted to the bracket. It's going to come with four screws and it's going to come with the washers and the nuts that you need to get the bracket . or the socket mounted to the four connections there on the mounting bracket. To go over the functions of the wires real quick. You can see here that it's going to expose a 4 way flat connector.

This is designed to plug into your existing 4 way, and then it's going to have four more wires that are exposed. All the wires are going to have butt connectors on them. The white wire's going to have a ring terminal on it for easy connection, so those are already in place, they're already installed and ready to be connected. Your white wire is going to be your ground wire. This is to be grounded to the vehicle frame. The yellow wire is going to be the center pole of the 7 way connector.

It's normally used for connection to the reverse light circuit. Your blue wire is for the connection of the electric brake feed from the brake controller. Then your black wire is going to be the twelve volt wire and will need to be ran to the positive terminal of the vehicle battery. It needs to be ran through a forty amp circuit breaker. That is going to be sold separately.

You can find that right here on our website with part number PK54540. This wire will be used to maintain the charge of a trailer mounted accessory battery and/or breakaway battery. Those already have the easy connectors on them that way all you have to do is make a few connections, get some wiring. If you need the full setup for installing a brake controller, all the additional wiring, you can use part number ETBC7. That's a kit that we here at Etrailer put together to make it easier for you. You can find that right here on our website. I want to focus here on the 7 way connector. It's got a spring loaded lid so when it's not in use it's going to remain closed that way it's going to protect the connection points on the inside. It's got the indicators here on this side. Each light has a code right next to it. The first one's going to be twelve volt. That's going to be for the twelve volt hot lead. If that's connected correctly and working properly that will light up. BK is the output from the brake controller so if you do not have a brake controller installed this light will not light up. The back up, BU, is for the reverse lights. If this circuit is not connected on the vehicle it will also not light up. RT stands for right turn. TM stands for the running lights or tail and marker lights, and then LT stands for left turn. The overall dimensions of the actual socket here is going to be . the housing that goes around the socket, that's going to give us a measurement of three and three eighths by three inches. Once you have it ready to be mounted with the bracket all you have to do is run your wires through here. It's going to fit around that socket portion back here really nicely. It's going to go right through the appropriate holes. It's going to make sure that all the mounting holes line up, and then you're going to take your 4 way flat, it's got a couple grooves on it that slide into the bracket face. Once you have those on you just push it in. It's going to hold it right there for easy connection. You're going to have your 7 way round connector right here, and then right next to it you're going to have easy access to the 4 way flat. That's going to do it for our review of part number C57674. This is the Curt Wiring Adapter converting from just your 4 way flat to both a 7 way round and a 4 way flat system. .


Questions and Comments about this Video


Morris M.
Does the BK LED (red light) on the 7 way connector stay lit dimly all the time? It lights up brightly when the brake is applied. Everything works other than that. Curt 57674
Etrailer Expert
Reply from Jon G.

A lot of brake controllers will send a small pulse of electricity back to the 7-Way to sense if a trailer is connected or not. From what you're describing I'm pretty sure that's what is going on. If the light was bright all of the time or if you connect a trailer and the brakes are constantly applied then that would be an issue.

Wiley B.
Numbers of additional parts are spoken too fast and not understandable.
Etrailer Expert
Reply from Jon G.

The additional parts mentioned in this video are the 40A Circuit Breaker # PK54540 and the Universal Wiring Kit # ETBC7 .

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