Wiring to King Pin

Instead of a 4-pin connector, consider using the same connector as from your tow vehicle to the 5er. That's probably a 7-pin.

Wire them the same, and that way if you ever need to tow the Mirage without the 5er, you don't have to worry about any adapters.

Hi guys thanks for the response. The trailer that Im towing is a 7x12 Mirage enclosed trailer. It does have LED brake tail lights but the rest of them are incandescent lights. So the reason for running to pin box( thanks for correcting me) was to have no after load. I have done the wiring directly at the end and why I want to run it up front as the lights on the tow trailer were extremely dim and I dont want that ..

If you are running LED lights on that rear trailer, you can tap right off the wiring to the taillights at the back of your 5er. LEDs won't pull enough to be a bother to the wire size.

Electric brakes however, should be at least 10 gauge all the way back to the pin box. your current 2 axle electric brakes are already maxing out the 10 gauge on the 5er.

Pin box is easy to get to through the forward cabinet and fish through to the pin box. If you just cant get it that way, you can drop down one side of that plastic pan under the bedroom.

X2 i also did it that way

RoyB wrote:
I haven't done this before but I think you should be able to get to all the wiring you need from the rear stop lights on the trailer.

Just tap into the wires for both STOP and SIGNAL lights and ground and route to a new brake receptacle like what is on the rear of your truck. a 4-way connector is probably all you need for the tow vehicle. I imagine one of the rear lights will have the bundle of wires feeding both rear lights fixtures. You should be able to fish your new wiring down to the bottom to a rear bumper area mounted receptacle.

Connecting in at the KING PIN area seems like an awful long way to run new wires.

Check with etrailer.com for the parts you might need for the new weather tight 4-way receptacle items.

Roy Ken

Exactly right. That is how I did mine. Guess the OP didn't say if he needed trailer brakes also. That would probably be a game changer. I didn't need a trailer brake tap for mine.

I haven't done this before but I think you should be able to get to all the wiring you need from the rear stop lights on the trailer.

Just tap into the wires for both STOP and SIGNAL lights and ground and route to a new brake receptacle like what is on the rear of your truck. a 4-way connector is probably all you need for the tow vehicle. I imagine one of the rear lights will have the bundle of wires feeding both rear lights fixtures. You should be able to fish your new wiring down to the bottom to a rear bumper area mounted receptacle.

Connecting in at the KING PIN area seems like an awful long way to run new wires.

Check with etrailer.com for the parts you might need for the new weather tight 4-way receptacle items.

Roy Ken

I suppose they are all different, but mine has an electrical box on the back side of the pin box (the king pin is the large pin that hangs off the bottom of the pin box.)

Here is the wiring information for proper connections.