The trailer wiring diagram shows this wire going to all the lights and brakes. If the lights on the tester function properly the problem is the trailer lights or harness and you need to some trailer lights troubleshooting.
4 Pin Trailer Light Wiring Diagram H1 Wiring Diagram
Wiring 4 prong trailer lights. Wiring configuration for trailer side marker lights. You must check the trailer manual to see if the wiring is correct but normally the white wire is called the ground wire while the brown wire is used for tail lights. Trailer wiring harness recommendation for a 2007 chevy colorado. Check for broken wires near the connector. On a 4 way flat trailer wiring harness white is the ground brown is running lights yellow is left turn signal and green is right turn signal. Also it must connect with things if included that use the aux power and back up lights too.
The most common wire thickness for a trailer is 16 gauge but i bought thicker wiring for added durability. Clean the connector photo step 2 below and check again. Wiring instructions for optronics 4 12 inch round trailer stop turn and tail light st40rb. Use a simple 4 way flat connector to power your 2 light trailer lights or use a custom vehicle specific trailer wiring harness. Lets see what types of connectors the trailer light wiring industry uses today. Harness has been overloaded due to excessive draw from lights or a short in the trailer wiring.
Buy a 4 pin wiring kit with wires at least twenty feet in length so its long enough for your trailer. Electric brakes sometimes this will be black wire in a double wire cord with the white. Wiring new 4 way connector on trailer with 5 wires. Depending on the size of your trailer and the number of lights you might want to check on the internet for the recommended gauge for your specific trailer. If you still have problems make an appointment to have the wiring checked. 7 pin this is an excellent in depth video on how to wire a 7 way round trailer plug that includes wiring diagrams.
Signal and brake. Some trailer builders just connect this wire to the frame then connect the ground from all the other lights and accessories to the frame as well. Trailer lights worked when the harness was first installed but eventually stopped working on one or all functions. Tow vehicle has amber turn signals separate. Installing the 4 pin trailer wires. Wiring new 3 wire light on trailer to replace 2 wire light.
While the basic configuration is a 4 way flat connector that features one female and three male ends you may come across connectors with up to seven pins for additional functions that require wiring including electrically actuated brakes power source for a winch etc. 4 pin this is one of the better videos we have come across that shows how to wire the tail lights on a utility trailer with a 4 way trailer wire connection. What is blue wire on trailer lights. Has separate bulbs for lighting stop and turn signals both red. Ground location for harness or trailer connector is weak or ground connection has loosened over time.
Gallery of Wiring 4 Prong Trailer Lights
