Need Help With Reverse Light Problem

[Disciple]

I have been wanting to put reverse lights on my trailer for sometime and did so this weekend. But they are not working.
I used the backup lights that 21XDC used from 4 State Trucks (https://www.4statetrucks.com//lighti...tion_40232.asp).
My trailer does not have brakes nor wiring for the brakes, so I ran a new wire and added a 5 pin flat connector for the backup function.
The brakes, turn signal, and tail lights all work; but not the reverse lights.
The new wire that I ran, I connected to the blue wire marked (BK) on the plug and the yellow pig tail on the light.
The 5 pin flat plug has the white ground wire, brown for the tail, yellow for left turn, green for right turn, and the blue wire. no purple like I see in the diagram from etrailer.
I hope someone can tell me where I went wrong.
If it makes any difference; my truck has a 7 pin round connector. I'm using a 5 pin flat with an adaptor.
The adapter has 5 receivers on the trailer side, 4 pins plus the the center pin on the truck side.
I thought I was smart enough do do this job; but maybe not.
Thanks

[mikeky]

Your 7 wire truck plug should have the reverse wire connected to it. Not sure how you are testing, but the reverse lights on my truck only work when the truck is running.

[Disciple]

The way I'm testing is for my wife to put the truck in reverse.
After writing my post, I have been thinking over my problem.
The lights I installed have tail, brake, turn, and backup all in the same 6" light assembly.
I hooked my truck to my trailer in the garage and had my wife operate the truck while I was at the back of the trailer.
She has the emergency brake on and her foot on the brake to make sure she does not back though the wall.
I'm now thinking the brake light is over riding the backup light.
I called 4 State Truck to ask them, they said it made sense but were not sure. I'll have pull it out on the street and check again tonight.
This may be a problem with using this type of backup light, because I know I'll have my foot on and off the brake as I'm backing.
Will see. I hope 21XDC will see this and give me more information about his.

[CatFan]

Look under the hood for a fuse for trailer backup lights before you chase it further.

[Disciple]

Look under the hood for a fuse for trailer backup lights before you chase it further.

Would that fuse be separate of the truck's backup lights?

[CatFan]

Would that fuse be separate of the truck's backup lights?

Yes.

[Disciple]

Going through the manual of my truck (Toyota). In the section on towing; is Service Connector For Brake Controller for towing package.
Your vehicle is equipped with a service connecter for the trailer brake controller. Link the connecter via the sub wire harness stored in the glove box ( this connects under the dash). Remove when not in use.
The detail drawing and diagram is not very clear. I crawled under the dash; but I don't see the connection. Called the Toyota service department; but I guess I'll have to take the truck in for them to look. But; this makes me think this is my problem.
Anyone know or have an idea before I pursue this route.
Nothing ever works out to be as simple as it seems.
Thanks for any and all help.

[CatFan]

Going through the manual of my truck (Toyota). In the section on towing; is Service Connector For Brake Controller for towing package.
Your vehicle is equipped with a service connecter for the trailer brake controller. Link the connecter via the sub wire harness stored in the glove box ( this connects under the dash). Remove when not in use.
The detail drawing and diagram is not very clear. I crawled under the dash; but I don't see the connection. Called the Toyota service department; but I guess I'll have to take the truck in for them to look. But; this makes me think this is my problem.
Anyone know or have an idea before I pursue this route.
Nothing ever works out to be as simple as it seems.
Thanks for any and all help.

tThe brake controller shouldn’t have anything to do with trailer lights.

[Disciple]

Thanks for answering CatFan. I'll go back to the fuses. This truck has four fuse boxes, and at least two have fuses marked towing. I'll to figure out the one for the trailer backup lights.

[wmitch2]

Check for power at the trailer plug in on the truck when the truck is in reverse. Your truck back-up lights should come on and you should show 12v at the trailer plug-in on the truck. It should be the Blue or Purple wire. If there is no voltage, then look for the fuse, it will be under the hood. Your owners manual will tell you which one it is, or a google search works too. Also, you do not have to have the truck running to test the light, just have the key on and the transmission in reverse, and the emergency brake on.

[mikeky]

Check for power at the trailer plug in on the truck when the truck is in reverse. Your truck back-up lights should come on and you should show 12v at the trailer plug-in on the truck. It should be the Blue or Purple wire. If there is no voltage, then look for the fuse, it will be under the hood. Your owners manual will tell you which one it is, or a google search works too. Also, you do not have to have the truck running to test the light, just have the key on and the transmission in reverse, and the emergency brake on.

My Chevy has to be running before the reverse lights come on. I didnt know until I was adding reverse lights to the trailer.

[catman2]

May be a little late for you since you already bought new lights but a better idea is to add independent back up lights and have them operate on a separate switch. I don't use reverse much when backing down a ramp. As soon as the boat crosses the incline I put the truck in nut neutral.

[Bullet[BS]]

Take a look at this diagram.
wiring-diagram-color-function.jpg
So, if you want back up lights on your 5 pin this is what you will have to wire it in yourself because your truck side will not put power to the yellow wire when in reverse.
If you look here you can do it yourself.
relay wiring.jpg
Or, open up your 7 round to 5 flat adapter and connect the center pin to your blue wire lug.

[mikeky]

OP, you said you have a 7 to 5 adapter but ran a separate wire? If so, and you don't have reverse power with the 5 pin adapter in the truck plug then you probably have a bad fuse as Catfan stated, or there is a problem with the truck's wiring. If the truck is wired properly and fuses are good then all you need is a 7 to 5 adapter.

[mikeky]

Take a look at this diagram.
wiring-diagram-color-function.jpg
So, if you want back up lights on your 5 pin this is what you will have to wire it in yourself because your truck side will not put power to the yellow wire when in reverse.
If you look here you can do it yourself.
relay wiring.jpg
Or, open up your 7 round to 5 flat adapter and connect the center pin to your blue wire lug.

He needs reverse power from the purple wire. That diagram tells you the blue wire goes to the breakaway switch. The blue wire goes to the trailer's electric brakes, it gets power from a brake controller. The breakaway battery and switch is then wired into the electric brake circuit so in case the trailer separates from the truck the breakaway battery takes over and applies power to the brakes.

The blue brake wire does not go from the truck plug to a 5 pin flat adapter, the purple wire does, but the wires coming from the actuator and the 5 pin are probably blue, and this can add to the confusion.

[Disciple]

Thanks for all the replies form everyone. I went back over everything, checking fuses to start with. Then reading diagrams and You Tube.
Finally I separated the truck and trailer and connected my lawn mower battery to the trailer with jumpers to check the trailer.
Long story shorter; I used bullet connectors to attach the 5 pin plug to the wiring, and wrapped it with braided cable wrap taped and ty wrapped.
Stripped the wiring down and found the bullet connector to the back up light disconnected. A dummy mistake.
My reason for backup lights was for getting home in the dark and backing a long ways to get in the garage, not the ramp.