Trailer Turn Signals Are Reversed

Question

Question:

I’ve been using my trailer and vehicle combo for over two years but it was pointed out the last time I was hooked up that my turn signals were reversed. They have worked fine since I had the harness installed but now all of a sudden it’s backwards. Thoughts?

asked by: Wayne

0

Expert Reply:

I've never heard of turn signals suddenly being reversed, but there are a number of possible causes. Just to verify, the first thing you'll want to do is use Cordless Circuit Tester # PTW2979 and test the connector on your vehicle after disconnecting it from your trailer. Check the wiring going into your harness from your tail lights to see if those wires are carrying the correct signals.

I'm going to assume they are but it's important to verify so that you can pin down the issue to the trailer (which is most likely). You will also want to check both your vehicle and trailer connectors for corrosion, which can be green or white in color. And interfere with the signals getting through the connectors so if it is present you are going to need to replace the plug with # 18004 for the trailer side or # 18252 for your vehicle.

After that trace your wiring to look for any wires on the trailer side that are nicked or damaged as that could have the signals bleeding into each other for some reason. Finally, double check your grounds at your lights, ensuring they are good and are attached to bare metal surfaces and free of any paint, dirt or corrosion. A bad ground can lead to all sorts of funky problems.

I have added a links below to a help article on trailer wiring, including a troubleshooting guide for you to take a look at. Additionally, to help prevent any type of corrosion in your connector, and increase its durability and lifespan I highly recommend using Dielectric Grease for Electrical Connectors # 11755.

expert reply by: Kyle S

0

Answer 1

It sounds like either his truck isn't wired correctly or your truck and trailer aren't wired correctly. This can be easily determined by using a circuit tester like part #PTW2979 to test the various functions. On a typical 4-Way the…

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Answer 2

It sounds like the wiring on your 2000 4Runner needs to be corrected so that the turn signal lights activate correctly and are consistent with the wiring on your other vehicles. First make sure the tail light connectors are installed on the correct…

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Answer 3

If your right turn signal is blinking with the left turn signal applied that most likely means you have a short between the right turn and left turn signal circuits or you possibly have the left turn signal shorted out to the running light circuit as…

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Answer 4

Sounds like you wired both your left and right turn signals to your right turn signal. To correct this you will need to rewire your trailer. Since trailer wire colors can vary (not usually) you will make sure you wire by function and not just color.…

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Answer 5

If you used a wishbone type of wiring on the trailer, it could be lending to the issue you are having. With a wishbone wiring harness on the trailer, the running light signal is split at the plug and carried down two separate wires; one for the left…

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Answer 6

It sounds like there are either some crossed wires or a bad ground (weird things can happen when there is a ground problem). On a trailer side 4-Way the covered pin is the ground. Next to it is the running lights. The third pin is left turn signal…

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Answer 7

In 7-way wiring the trailer brake circuit's contact/pin is next to the contact for the right turn/stop circuit. What can happen is that corrosion can build up on or inside either the truck socket or the trailer plug and this corrosive build-up…

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Answer 8

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…

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Answer 9

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…

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Answer 10

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…

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Answer 11

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…

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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…

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