7 way trailer pin has no 12v

Hello
Tried to hookup a Bluetooth brake adapter. It won’t work because apparently it doesn’t have a 12v
Is this true? And how to I get 12v to the 7-way?

 

The 7 way should have 12v power, but it is switched with the ignition.



I should add - is your wiring harness factory? Or aftermarket? And have you checked fuses?

 

It is factory and it dose not have 12v. I checked the fuses under the hood and it has relays but dose not work 12v for my new
CURT Bluetooth-enabled “Echo” Trailer Brake Controller.
Is there supposed to be a dedicated 5A fuse to run the two relays for the trailer plug

 

I would pull out the multi-meter and start checking pins, connectors, fuses, relays, etc. With the vehicle running, check to verify whether or not you have 12v battery power at the truck connector. Might as well check the other pins as well to make sure lights and turn signals work. There are several towing related fuses under the hood. Your layout may be a little different than my '21, but I believe that the 30A Towing fuse in yellow is the 12v power at the plug.

The factory 7way RV plug does have switched 12v power. If it were on constantly, it would drain the battery whenever you have a travel trailer or trailer with it's own electrical demand hooked up with the truck off. For example, if I hook up my travel trailer, it will charge the TT batteries while the truck is running. My enclosed trailer, however, doesn't have it's own battery, so the interior lights on the trailer only work with the truck running; once I turn the vehicle off, the lights inside the trailer are no longer powered.

I'm unfamiliar with the Curt Bluetooth trailer controller. If you decide to switch back to a conventional trailer brake controller, Toyota prewired everything under the dash (well, in the drivers side footwell, really) so all you need is a simple pigtail to wire in a brake controller.

 

Silly question, but is the ignition turned on?
Mine has 12v but only when the key is turned to “ON”

 

Hahahaha
I wish it was that easy. Yes turned on with truck running.
I guess I just need to know if all 2007-2013 tundras have power out the back plug?
I’ve hooked up trailers and all my lights work as they should. It just seems like I’m missing the 12v
Chat gpt tell me a lot of things that didn’t check out. One was that there might be a wire capped off beside the positive made for the 12v for the trailer plug

 

If it is a factory plug, yes, it has 12v power to the 7 way RV. I have a '13 tundra, a '21 tundra, and a '15 sequoia - all equipped with factory tow package. All have switched 12v power at the plug at the back of the truck.

 

Ya
I don’t get it. I’ll check with a multi meter and the fuse. what size fuse is it?

 

There are a few. Please see the pic that I posted. Your fuse box lid will have the correct sizes listed.

 

So check the 6 fuses and if there all good. Then what? Check the wires going into the plug? Or is there something else I could check

 

Yes, I would check all of the fuses and probably just replace the 30 Amp trailer fuse I circled in yellow. Then, using your multimeter set to DC voltage (dashed and dotted line, not wavy line), start at the plug at the rear of the vehicle and identify the correct pins for power, tail lamps, blinkers, etc. If you start with tail lamps, for example, you can verify that your multimeter is working correctly and that you have it grounded properly. Work your way up the line to each connector to trace where you do or don’t have power for the pin in question.

 

Ok
I’ll try that when I get off work.
thank you for all your help. I’ll keep you posted

 

Your diagram is different then mine
I checked the 30A. And all the other fuses just don’t know how to check the relays

 

Well
I pulled the plug and returned the blue tooth brake transmitter. I tried everything and on doing so. Something happened to my truck. I when’s to start it because I had the key on and blinkers. Testing the plug. But when I went to start the truck. It turned over and over and over. But would not start! And when I let go of the key. The starter kept turning over for 5 seconds or so. Tried it a few times still did the same thing. Would not start and start lagging.
I disconnected the battery for 30 minutes and still did the same thing but killed the battery ( which is only 1 1/2 years old). Boosted it….still same issue. Put it on a battery charger then hooked up a code reader. Hoping it has nothing to do with the ecm. Didn’t show anything alarming. For shits and giggles I tried to start it and she started right up!!!
Don’t get it twisted

 

The easiest way to figure if the truck's trailer plugs are working properly is by using a 7-Way tester with LED's, or a 4-way tester for the 4-way flat plug. Regardless for the LED that uses the 12 volts to energize or turn on, it uses the truck's ground wire.

Otherwise you can connect the trailer's plug to the truck (7-way or the 4-way one, whichever the case may be), and have someone letting you know if the brake lights, turn signal, and other lights are working. Regardless, both the trailer and the truck still need the same ground, one on the truck's frame and another point on the trailer's frame. The ground signal between the trailer and truck travels through the trailer and truck plugs.

 

Bought one
Should be here in a couple days

 

I just don’t get it. As I have looked at the wires going into the back of the plug. Everything looks good. Fuses are good. Checked with a multi meter. Shows all turning signals running lights. Just dead where the power prong is. Nothing there