Model Y Brake Controller

[LNL_HUTZ]

Ditto for the San Francisco service location. I made a mobile service appointment through the app and included the part number for the pigtail in the notes. A couple days later, a tech got back to me to say that they won't come out and plug it in, but I can pick it up any time. None of the local Tesla techs at first seemed to know why I would need a MX part for a MY, but they figured it out and were super helpful. I stopped by, paid the $4, yada yada yada, now the spliced wire harness is ready for me to finish installing the P3 tomorrow. As a colorblind American, I found it extra entertaining that three of the four wire colors don't match, but it's easy enough to figure out what goes where. Thanks to TMC, I figured out that it just isn't that big a deal to put in a regular controller like the P3 in a MY, instead of having to futz with something wireless like the Curt.

 

[LNL_HUTZ]

Some pictures of my completed Tekonsha P3 installation. On the whole, this is not a difficult project. Plugging in the pigtail is a pain, but with patience and some sweet talk, the opening got just big enough to work my hand in.

 

[dduffey]

Installed the P3 on our MY. I used the existing black screw that is above the foot rest and automotive double sided tape for good measure. It makes it a bit harder to reach but not impossible, was able to still calibrate the trailer.

Regen does not enable the brakes (it does enable the brake lights), so you should be aware that regen while turning in poor conditions (road/weather/load) could cause jack knifing as the trailer pushes the slowing car.

For that reason I am using boost if I tap the brakes in the car the P3 starts at a higher voltage immediately. And in general I feel that if I am touching the brakes I am already past the point of regen and really do want mechanical help in slowing down and it makes sense for the trailer to help.

 

[LNL_HUTZ]

Seems like Trailer Mode should automatically put you in Low Regen, to make the braking experience more like an ICE.

 

[knel216]

This thread has been super helpful to me as I went through my Model Y purchase, so I wanted to share my success story in getting the 4-pin brake controller cable. First, knowing from this thread that obtaining the cable might be an issue, and since the Tesla delivery center is more than an hour and a half from home, I wanted to make sure I had done everything I could to make sure I wasn't going to walk away from the delivery without it. I started by emailing my sales advisor asking whether or not the cable would be included with the car (per the owners manual). He referred the question to his manager, who initially told me it was included, then emailed back a couple of minutes later and said that it wasn't. After a couple of back and forth emails, they committed to resolving it at delivery. Before the delivery was complete, I explained the situation to the delivery specialist, who initially tried to tell me the "wires" were already installed (she was referring to the 7-pin connector at the hitch), but after a little more discussion we finally came to an understanding. I think what helped most what that I was able to provide her with the part number from this thread (1072586-00-A). She made the trip over the parts department and had the cable for me within 5 minutes. FWIW, this was the Tysons, Virginia location, my vehicle was a Feb 14, 2021 build, and the delivery was on March 12, 2021 (so it would seem that corporate Tesla still hasn't straightened this out). Overall, the delivery was very smooth, and we're looking forward to taking our Model Y and a small travel trailer out camping this summer. Thanks to everyone who contributed to this thread!

This has been SUPER helpful. I, too, am waiting on my MYLR delivery w/tow package. I plan to pull a small travel trailer and want to get everything sorted.

Sounds like my next steps are to contact my sales consultant with the right pigtail part (1072586-00-A) to get things rolling. I will be taking delivery from my local SC but don’t have a contact there, and wouldn’t know where to start. I’m some time from delivery (about two months these days!!)

Meanwhile I’ll do some research on the actual brake controller and setup; a few have been mentioned in the thread. I am usually a big fan of wireless but since there appears to be minimal effort (assuming I can get the pigtail) to do a wired setup, that’s the way I’ll go.

Also sounds like regen alone does nothing to the TT brakes but when the lights engage the brake lights on the TT will, too. If I want the brakes to engage on a heavy regen situation I need to take over and touch the brake pedal - do I have that right?

This thread has been super helpful. There aren’t a ton of resources out there on trailering with a MY just yet so I’m thankful this exists.

 

[dduffey]

This has been SUPER helpful. I, too, am waiting on my MYLR delivery w/tow package. I plan to pull a small travel trailer and want to get everything sorted.

Sounds like my next steps are to contact my sales consultant with the right pigtail part (1072586-00-A) to get things rolling. I will be taking delivery from my local SC but don’t have a contact there, and wouldn’t know where to start. I’m some time from delivery (about two months these days!!)

Meanwhile I’ll do some research on the actual brake controller and setup; a few have been mentioned in the thread. I am usually a big fan of wireless but since there appears to be minimal effort (assuming I can get the pigtail) to do a wired setup, that’s the way I’ll go.

Also sounds like regen alone does nothing to the TT brakes but when the lights engage the brake lights on the TT will, too. If I want the brakes to engage on a heavy regen situation I need to take over and touch the brake pedal - do I have that right?

This thread has been super helpful. There aren’t a ton of resources out there on trailering with a MY just yet so I’m thankful this exists.

Sort of. If wired correctly the brake lights of the car will control the brake lights in the trailer even when just regen.

The brake switch (pedal) will control the brakes (physical) on the trailer. If this is not happening like this then it is mis-wired.

Think of the the brake lights and physical brakes as separate circuits (because they are).

 

[Npalumbo89]

Are you leaving regen on or off while towing? The RV Center that I’m going through to buy my trailer would not install the break connector into the Tesla did not want to take the risk. Tesla would not install anything that is not an official Tesla branded component. So I’m going with a Bluetooth controller for my trailer. I’m just curious about the region breaking and whether or not I need to turn it off or adjust it.

 

[MP3Mike]

Are you leaving regen on or off while towing?

There is no option to disable regen on current Teslas. (At least I'm pretty sure there isn't.)

 

[Npalumbo89]

There is no option to disable regen on current Teslas. (At least I'm pretty sure there isn't.)

I didn’t word that correctly apologies. I meant adjusting the stopping mode. Creep vs hold and Roll. Not sure if they make any difference or affect the brake controller/trailer brakes.

 

[Npalumbo89]

There is no option to disable regen on current Teslas. (At least I'm pretty sure there isn't.)

Are you leaving regen on or off while towing? The RV Center that I’m going through to buy my trailer would not install the break connector into the Tesla did not want to take the risk. Tesla would not install anything that is not an official Tesla branded component. So I’m going with a Bluetooth controller for my trailer. I’m just curious about the region breaking and whether or not I need to turn it off or adjust it.

To clarify I didn’t mean turning off regen as that is not possible. I’m just looking to see if any of the stopping modes will affect the trailer brakes and brake controller and if any of them would be better for towing.

 

[MP3Mike]

I didn’t word that correctly apologies. I meant adjusting the stopping mode. Creep vs hold and Roll. Not sure if they make any difference or affect the brake controller/trailer brakes.

Ok, the "Roll" mode doesn't normally reduce regen until you are already mostly stopped.

The manual doesn't mention any change to regen when using Trailer mode.

 

[THE_KINGDOM]

In the same boat looking for a connector, thanks for the part number, I'll give our service center a call.

BTW, these braking controllers that use your smartphone just for the accelerometer seem silly. Those are cheap parts nowdays, maybe cheaper than the bluetooth chip to connect to the phone. Weird.

Wrong, the Curt echo does not use your smartphone for the accelerometer, that would be absolutely ridiculous, as you likely move your cell phone around during the course of a several hour drive. It only connects to your phone for Bluetooth to modulate the breaking dynamics just like a head unit with other wired solutions.
The Curt Echo has a three-way accelerometer within the chassis of the plug itself, which plugs into the 7-way trailer connector

 

[Shevek]

Wrong, the Curt echo does not use your smartphone for the accelerometer, that would be absolutely ridiculous, as you likely move your cell phone around during the course of a several hour drive. It only connects to your phone for Bluetooth to modulate the breaking dynamics just like a head unit with other wired solutions.
The Curt Echo has a three-way accelerometer within the chassis of the plug itself, which plugs into the 7-way trailer connector

Do you find that the Echo works well? I'm.wondering how the wireless trailer brake interacts with Regen.

 

[unwarrantd]

I know this thread is a bit old, but maybe someone will be ablate answer this for me. I can't find it clearly anywhere online so far. Is the 12v on this 4 pin connector switched with occupant sensor, with sentry mode power, or is it a truly 12v constant that is not switched at all? Does it stay on when not in trailer mode? Looking for an occupancy switched 12v for the car so I don't need to tap a relay. I've never used a brake controller so I don't know if it is expected to be on when parked or not. Thanks!

 

[yvr_my]

I know this thread is a bit old, but maybe someone will be ablate answer this for me. I can't find it clearly anywhere online so far. Is the 12v on this 4 pin connector switched with occupant sensor, with sentry mode power, or is it a truly 12v constant that is not switched at all? Does it stay on when not in trailer mode? Looking for an occupancy switched 12v for the car so I don't need to tap a relay. I've never used a brake controller so I don't know if it is expected to be on when parked or not. Thanks!

From all my research this is a reliable 12v switched power source. I actually just picked up the harness from my local Tesla Service Center as I plan on using it to power a couple accessories. I should have my MY 2023 shortly and can post back to confirm.

 

[karxius]

Reviving older thread.
I am trying to tap into 12v power for accessories on my ‘23 model Y. I bought 4-pin pigtailfor white connector from Tesla but seems like red/12v pin is dead either I am in the seat and have car activated or if I am out of it. Only pin that draws power is brake singal once I step on the brakes.
Is there something trailer-wise that needs activating for this pin to have power?

Thanks!

 

[MP3Mike]

Is there something trailer-wise that needs activating for this pin to have power?

It may only power it when it detects a trailer hooked up. Do you even have the towing package?

 

[Webeevdrivers]

Reviving older thread.
I am trying to tap into 12v power for accessories on my ‘23 model Y. I bought 4-pin pigtailfor white connector from Tesla but seems like red/12v pin is dead either I am in the seat and have car activated or if I am out of it. Only pin that draws power is brake singal once I step on the brakes.
Is there something trailer-wise that needs activating for this pin to have power?

Thanks!

The 12 volt pin on pin 4 of the connecter on 2023 teslas (with 16 volt battery) is disabled. It’s disabled because feeding 16 volts to the trailer battery (which is probably 12 volts) would cause the trailer battery to overcharge.

Hope that helps.

 

[MP3Mike]

The 12 volt pin on pin 4 of the connecter on 2023 teslas (with 16 volt battery) is disabled. It’s disabled because feeding 16 volts to the trailer battery (which is probably 12 volts) would cause the trailer battery to overcharge.

I'm pretty sure he was talking about the brake controller connector under the dash, not the trailer connector at the back of the vehicle.

 

[karxius]

Thanks for replies.
No tow package, and correct - I meant white brake controller connector (4 pin) in left (driver) footwell.
Is there any chance to activate it? If not would appreciate any footwell-located tap-in spots for 12v suggestions.