Installing Hidden Trailer Brake - Redarc Tow Pro Elite

[drwerner1001]

I ordered my 2023 MYLR with the factory tow hitch. I expected the hitch and wiring to perform like all the other tow vehicles I have had (I was coming from a BMW X3). Nope. Tesla does not supply 12V+ power to pin 4 due to the upgraded Li-ion battery:

This means that a brake controller like the Curt Echo or Prodigy RF Won't work - as they require power from the 7-way. Unfortunately, I have both. So, now I need a third. There are many that attach under the dash, but I don't like how they look or that I need to take them on and off as I need or don't need them. The other issue is that if your trailer uses pin 4 to charge a battery or run anything on your trailer while you are towing, you are out of luck.

I purchased a Redarc Tow-Pro Elite:

I installed it behind the driver side left kick panel (which you need to open to get to the wiring harness):

I used part Tesla Wire Harness Part Number 1072586-00-A with lever wire nut connectors which allow for easy, secure connections and the ability to connect 1 to 2 (my V1 is connected to the same power):

I mounted the controller to a flat metal part of the vehicle behind the kickplate and after it was tested and buttoned up, I didn't want to drill holes, so I used 3M tape to mount the switch to an inconspicious area on the left side of the dash where it is easy to see and reach:

Now, I can keep the controller up and available where it doesn't bother me

 

[el-guapin]

Nice!!... THNX 4 sharing!

 

[ewoodrick]

I ordered my 2023 MYLR with the factory tow hitch. I expected the hitch and wiring to perform like all the other tow vehicles I have had (I was coming from a BMW X3). Nope. Tesla does not supply 12V+ power to pin 4 due to the upgraded Li-ion battery:



This means that a brake controller like the Curt Echo or Prodigy RF Won't work - as they require power from the 7-way. Unfortunately, I have both. So, now I need a third. There are many that attach under the dash, but I don't like how they look or that I need to take them on and off as I need or don't need them. The other issue is that if your trailer uses pin 4 to charge a battery or run anything on your trailer while you are towing, you are out of luck.

I purchased a Redarc Tow-Pro Elite:

View attachment 1057847

I installed it behind the driver side left kick panel (which you need to open to get to the wiring harness):



I used part Tesla Wire Harness Part Number 1072586-00-A with lever wire nut connectors which allow for easy, secure connections and the ability to connect 1 to 2 (my V1 is connected to the same power):


I mounted the controller to a flat metal part of the vehicle behind the kickplate and after it was tested and buttoned up, I didn't want to drill holes, so I used 3M tape to mount the switch to an inconspicious area on the left side of the dash where it is easy to see and reach:



Now, I can keep the controller up and available where it doesn't bother me

That's one of the cool things that's in the Cybertruck that gets very little mention. It comes with a built-in trailer brakes controller and is included in the UI. It even has a railer light test button in the UI!

 

[alain99]

And getting 12v to pin 4 would not have worked?
You could use a DC-DC step down converter to convert the 16v to 12v needed.

 

[drwerner1001]

And getting 12v to pin 4 would not have worked?
You could use a DC-DC step down converter to convert the 16v to 12v needed.

I wish it was that easy. I thought about it. Others have tried without full success - or at least opening the door to another problem. I spoke to Tesla and they hinted a solution is in the works. I still need power there to charge my battery.

 

[ewoodrick]

And getting 12v to pin 4 would not have worked?
You could use a DC-DC step down converter to convert the 16v to 12v needed.

I believe that the issue is more focused around the current requirements. Some trailers have significant current requirements at 12V, sometimes this is actually hooked up to the trailers 12V battery bank.
This sometimes causes fuses to be blown in conventional towing arrangements, but the general problem is that the 12V usage in the trailer is not well defined and sometimes abused.

 

[TesLEEZ]

Have you connected this to a trailer yet to see that it works?