Troubleshooting Trailer Running Light Circuit that Comes on When Trailer Wiring is Plugged In

Question

Question:

When I plug into pick up, tail lights turn on - on pick up and 5th wheel. Also the back up lights turn on only on the pick up. I rewired the pick up and checked circuits making sure they all work as they should. Suggestions? Thank you

asked by: Kite M

1

Helpful Expert Reply:

You have a short between the 12 volt running light circuit of your trailer's wiring and the running light circuit. This is causing the voltage from the 12 volt circuit to backfeed onto both the trailer and truck. You need to check out the connector of the trailer on the front and back looking for any exposed wire or corrosion and fix as needed.

expert reply by: Jameson C

1

click to enlarge

Answer 1

When wiring a trailer connector, it is best to wire by function, as wire colors can vary. We have an excellent wiring diagram on our website, I will provide you a link so you can look at it. If you are looking at the inside of the trailer connector…

view full answer...

Answer 2

The Chevy Vans are not actually pre-wired for a brake controller. A brake controller has to be partially hardwired in. If your 2007 Chevy Express came with a factory installed 7-Way trailer connector then the blue brake output wire should be ran from…

view full answer...

Answer 3

I have a few things for you to check when it comes to not being able to pair your iPhone with the Curt Echo #C51180. The first thing to do is make sure that you're pairing your phone with the Echo through the app. If you paired it through the…

view full answer...

Answer 4

According to my research the following wires for the 7-Way on your 2019 Chevy Silverado 2500 should carry the following functions: Green OR White/Green - Reverse White - Ground Blue - Brake Controller Green OR Green/Purple - Right Turn/Stop Red/Black…

view full answer...

Answer 5

A 4-Way trailer connector has the basic lighting functions only; running lights, left turn signal and brake lights, right turn signal and brake lights, and ground. A 7-Way has these functions and a 12 volt circuit, a circuit for electric trailer…

view full answer...

Answer 6

In order to determine the torque rating for the lug nuts on your trailer you will need to know check out the chart I attached that shows all of the torque specs for all the trailer lugs available based on stud size, wheel material and wheel size.

view full answer...

Answer 7

Lance does have a proprietary plug, but many customers see a standard 6-way or 7-way round and notice it doesn't fit their factory 7-way as well. I've attached an article to help if you have one of the 7-way or 6-way round connectors which we…

view full answer...

Answer 8

If your trailer has 7 wires running all the way back to the brakes, then yes, you can tap into the existing wiring. Each of your new brakes will have two wires for the brake magnet. One wire is for 12 volt power to the brake magnets and the other…

view full answer...

Answer 9

It could be a tow package fuse on the vehicle. Use the owners manual to find the locations of fuses/relays related to the tow package wiring to check them and replace as needed. If the issue is not a fuse or relay then you can test the vehicle side…

view full answer...

Answer 10

Traditionally, trailer manufacturers did not use electric brakes on boat trailers because the brake magnet wiring and trailer wiring did not always have the best insulation or water protection. These days, more and more manufacturers are using…

view full answer...

Answer 11

The difference between the Class II and Class III hitches has to do with their Gross Trailer Weight (GTW), their Tongue Weight (TW), and their Hitch Receiver Size. Class II trailer hitch receivers have a 1-1/4 inch receiver and can be rated up to…

view full answer...

Answer 12

Since wire color codes are NOT universal, we always recommend wiring by function, rather than wire color. If you look at the Trailer Wiring FAQ article I have linked you to, you can see some diagrams showing the proper way to wire a vehicle and…

view full answer...

Troubleshooting Trailer Running Light Circuit that Comes on When Trailer Wiring is Plugged In

Product Page this Question was Asked From

Featured Help Information

Miscellaneous Media

Continue Researching