Tow hitch, electrical connection and in cab brake controller

[Luke42]

I sincerely hope it isn't a mechanical switch... It should be through the Touch Screen.

Even my 2004 Porsche Cayenne Turbo handles the braking through it's towing computer, no brake booster needed.

This comment makes me concerned that you don't know how to use a trailer brake controller, and that you don't know what the manual trailer-brake activation switch is for.

Background: Here's what a trailer brake controller looks like:
https://www.tekonsha.com/product/90160_trailer-brake-control-proportional

Background: It has two primary controls: a trailer brake power adjustment (so that the trailer brakes get the right amount of force when you activate the vehicle brakes), and a switch to activate the trailer brakes manually and independently of the vehicle brakes. This must be mounted within easy reach of the driver, so that they can manually activate the trailer brakes in a hurry.

The brake switch on the tow brake controller switch has two functions:

• To test the trailer brakes independently of the vehicle's brakes, as part of your departure checklist.
• To provide trailer sway control / jackknife prevention in emergency situations. When the tail wags the dog, you put on the trailer brakes to straighten out your combination vehicle.

I once towed an improperly balanced trailer, and that was a lesson learned --so I'm now consistent about balancing my trailers. I also saw someone almost get dumped over by wind-induced trailer sway on one of my first RV trips. As a result, I practice being able to get the trailer brakes on in a hurry -- which means reaching for the trailer-brake switch at a moment's notice.

The Tesla screen controls are great for things that might be changed by software, and tasks that aren't time-sensitive, at least in my experience. While Tesla's minimalism gets some things wrong, I'm a fan of the center-screen in my Model Y for the most part.

Configuring the tow brake controller on the screen would work just fine, but setting the gain isn't why you have the physical switch.

Screen controls are lousy for activating brakes in a hurry when the tail is wagging the dog. Towing safely requires that you be able to activate the trailer brakes independently and instantly, and a physical control on the dashboard is how that happens.

While Tesla is likely biased toward omitting the trailer brake switch, I'd be pretty reluctant use a vehicle without one for serious towing.

P.S. My Model Y also needs physical switches for windshield wipers and headlights, because the automatic controls sometimes get it wrong.

 

[HaulingAss]

Seems like something that could be automated.

-Crissa

No kidding. My 2010 F-150 has the towing package which includes a factory installed manual trailer brake controller. It's far from ideal for the driver to need to squeeze that brake controller while driving and there is plenty of room for error if you don't know exactly what you are doing.

Automation can handle it, probably without even needing a remote sensor suite on the trailer. Tesla will probably employ the rear camera on the Cybertruck to monitor the trailer (along with the solid state gyros that all Tesla already have). Tesla knows they can develop those systems as they ramp production because demand is never a problem that early in a products lifecycle. As the ramp progresses to ever increasing volumes, Tesla knows they need to continually add more value to keep selling the higher volumes. That's because this is primarily a software based solution that can be retroactively applied to vehicles already in the wild.

 

[Rutrow]

Seems like something that could be automated.

-Crissa

Theoretically and optimistically... Sure. But my extensive experience with FSD beta is that Tesla's autonomous driving computer today is no where close to the finesse and judgement that is needed for emergency control to counteract sway and fishtailing in different surface conditions. I have let FSD beta handle rain slicked, snow and ice covered roads in situations where if it screws up it won't damage the car, and it has failed MISERABLY >90% of the time. The current version won't even dodge pot holes or paint cans in the road during ideal weather. I'm hoping that higher resolution cameras of HW4 might help that. Dodging things in the road in slippery conditions demands high acuity at considerable distances to initiate a gradual swerve away that won't cause the tires to loose traction. I'm know the current cameras can't do that, and I fear that even 5 megapixel cameras will fall short.

I think an automated system may be able to outperform someone with little or no experience with emergency trailer maneuvers, but a human with lots of experience in rain, snow, ice, mud, ruts, washboard, etc. will outperform current and near future automation. This is why the performance versions of Teslas today have "Track Mode". Excellent drivers with intimate knowledge of track banks, cant, dips, humps, texture for given temperatures and temporary slick spots can easily out perform computerized traction control.

I am reluctant to say that computerized systems will never beat us at these tasks, but my understanding* of the brain makes me skeptical. We sell ourselves short in thinking that computers can beat us at everything, but when you realize the myriad of ways that an infant can reflexively outperform supercomputers at VERY simple tasks should increase your skepticism too.

*by "understanding" I mean our dearth of understanding about HOW the brain does what it does. To anyone interested in the brain, I HIGHLY recommend "On Intelligence" by Jeff Hankins and Sandra Blakeslee. It explains the difference between how brains and computers work and why faster, more powerful computers will never be the solution to A.I. No computer today can access its memory faster than the human (and other) brains can.

 

[scottf200]

Seems like something that could be automated. -Crissa

Since you didn't quote anything it is unclear what you are referencing.
Trailer braking has always required fine tuning the 'gain' (ratio of applied trailer braking) to balance how hard the trailer brakes are working compared to the vehicle. This is at various speeds and various trailers (multiple axles? weight? tire friction/wear? trailer brake type).

Ford knows their $hit and had a lot of experience. Impressive how much they take into acct. Experience that Tesla does not have but could copy.

 

[Crissa]

Since you didn't quote anything it is unclear what you are referencing.
Trailer braking has always required fine tuning the 'gain' (ratio of applied trailer braking) to balance how hard the trailer brakes are working compared to the vehicle. This is at various speeds and various trailers (multiple axles? weight? tire friction/wear? trailer brake type).

Ford knows their $hit and had a lot of experience. Impressive how much they take into acct. Experience that Tesla does not have but could copy.

Yes, this seems to be because you don't have any actual input from the brake pedal other than 'on' or 'off'.'

And so you're setting it like I do the regen on my Zero when I add it to my front brake.

-Crissa

 

[Neo]

This comment makes me concerned that you don't know how to use a trailer brake controller, and that you don't know what the manual trailer-brake activation switch is for.

Background: Here's what a trailer brake controller looks like:
https://www.tekonsha.com/product/90160_trailer-brake-control-proportional

Background: It has two primary controls: a trailer brake power adjustment (so that the trailer brakes get the right amount of force when you activate the vehicle brakes), and a switch to activate the trailer brakes manually and independently of the vehicle brakes. This must be mounted within easy reach of the driver, so that they can manually activate the trailer brakes in a hurry.

The brake switch on the tow brake controller switch has two functions:

• To test the trailer brakes independently of the vehicle's brakes, as part of your departure checklist.
• To provide trailer sway control / jackknife prevention in emergency situations. When the tail wags the dog, you put on the trailer brakes to straighten out your combination vehicle.

I once towed an improperly balanced trailer, and that was a lesson learned --so I'm now consistent about balancing my trailers. I also saw someone almost get dumped over by wind-induced trailer sway on one of my first RV trips. As a result, I practice being able to get the trailer brakes on in a hurry -- which means reaching for the trailer-brake switch at a moment's notice.

The Tesla screen controls are great for things that might be changed by software, and tasks that aren't time-sensitive, at least in my experience. While Tesla's minimalism gets some things wrong, I'm a fan of the center-screen in my Model Y for the most part.

Configuring the tow brake controller on the screen would work just fine, but setting the gain isn't why you have the physical switch.

Screen controls are lousy for activating brakes in a hurry when the tail is wagging the dog. Towing safely requires that you be able to activate the trailer brakes independently and instantly, and a physical control on the dashboard is how that happens.

While Tesla is likely biased toward omitting the trailer brake switch, I'd be pretty reluctant use a vehicle without one for serious towing.

P.S. My Model Y also needs physical switches for windshield wipers and headlights, because the automatic controls sometimes get it wrong.

My Cayenne has all of this built into it’s towing computer, it sense inertia and automatically adjusts the signal to my trailer’s brakes.
What I’m saying is the system be tunable through the touch screen, not manually used. I’m specifically saying I hope they don’t use the tech from the 60’s…

 

[Luke42]

My Cayenne has all of this built into it’s towing computer, it sense inertia and automatically adjusts the signal to my trailer’s brakes.
What I’m saying is the system be tunable through the touch screen, not manually used. I’m specifically saying I hope they don’t use the tech from the 60’s…

Where's the part where you check your trailer's breaks as part of your departure checklist?

 

[Neo]

Where's the part where you check your trailer's breaks as part of your departure checklist?

I'm not sure what you're asking? I think because with the 50's style external brake controller you can manually press to engage only the trailer brakes, you can brake the car using the trailer brakes alone, to verify that they are working? My Grandpa did that with his system.

Yeah, I can't do that.

What I do check is that the lights function through my onboard trailer cameras. I suppose I would be able to tell if the Porsche wasn't able to brake effectively if the 6,000lb trailer's brakes weren't working.

I guess I could install a camera pointed to one of the disc calipers so I could visually see it clamping onto the disc, that might be a descent safety add-on.

Honestly, the Porsche handles towing so well, it is really difficult to feel I'm towing Taj-Ma-Haul. When a semi passes me I do get a slight movement, so I'm investigating a B&W Trailer Hitches Continuum Weight Distribution Hitch.

Cheers,
Neo

 

[Neo]

I guess I could install a camera pointed to one of the disc calipers so I could visually see it clamping onto the disc, that might be a descent safety add-on.

Hmm, I just checked and the brakes are drum, so that won't work.

 

[Crissa]

Hmm, I just checked and the brakes are drum, so that won't work.

You can't see the action on the drum brake? Usually you can see the clamp from the back (axle) side unless they're fully enclosed... You could place a pressure or piezo sensor on the brake line to detect the action.

-Crissa

 

[Luke42]

I'm not sure what you're asking? I think because with the 50's style external brake controller you can manually press to engage only the trailer brakes, you can brake the car using the trailer brakes alone, to verify that they are working? My Grandpa did that with his system.

Yeah, I can't do that.

What I do check is that the lights function through my onboard trailer cameras. I suppose I would be able to tell if the Porsche wasn't able to brake effectively if the 6,000lb trailer's brakes weren't working.

I guess I could install a camera pointed to one of the disc calipers so I could visually see it clamping onto the disc, that might be a descent safety add-on.

Honestly, the Porsche handles towing so well, it is really difficult to feel I'm towing Taj-Ma-Haul. When a semi passes me I do get a slight movement, so I'm investigating a B&W Trailer Hitches Continuum Weight Distribution Hitch.

Cheers,
Neo

I made some dangerous mistakes when I was first towing.

It's clear you haven't learned the same lessons I have. Towing should be a separate endorsement on your driver's license, like a motorcycle license.

I'm a computer engineer, and I love high tech approaches to things - but you're putting all of your faith in Porsche's computer, and you're missing some fundamental things that the computer cannot possibly address, which must absolutely be handled at the level of basic physics.

Things you need to know:

1. Balance: The trailer must be balanced. The rule of thumb is that about 15% of the trailer's weight should be on the tongue, and the rest on the wheels. If the center of mass is too far forward, your car's suspension wont be able to handle the load. If the center of mass is too far backward, the trailer can swing your car around like a ragdoll once there is sufficient energy in the system. The only thing any computer can do when this happens is to put on the brakes.

2. Brakes: The trailer brakes must work. In the USA, the rule of thumb is that trailers over 2000lbs require trailer brakes. This is why you manually activate the trailer brakes when you start driving (your "departure checklist") to see if they work. Please RTFM in your car's owner's manual to see how to do this with your factory brake controller -- every factory brake controller I've ever seen on has a way to test the trailer brakes so that you can feel the deceleration they apply to your vehicle to make sure they work. The computer in your car can't help you with checklist discipline.

3. Checklists: Inspect your trailer for problems every time you tow to ensure that tires are properly inflated, brakes work, lights work, all trailer doors and cargo are stowed correctly, towing hardware is good, and so on. This is the "departure checklist" that I referred to. Checklist-discipline is critical.

4. Europe: Something else you need to know: the rules for towing are quite different in Europe than they are in the United States, and your car was designed by engineers with experience on German roads. What you need to know about this is that European roads have a separate speed limit for combination vehicles, and that rarely exceeds 100km/h (about 60MPH). Also, European traffic laws also require working trailer brakes on much smaller trailers than we do here in the USA, and a less litigious culture. As a result, tow ratings on European cars are higher than they are for equivalent American cars. RTFM in your car's owner's manual to to see what constraints Porsche puts on you when you tow.

Nobody taught me this stuff when I first started towing. Fortunately no people or equipment were damaged when I learned this, but I was a lot closer to disaster than I thought at the time. We really should have a formal method for teaching this stuff to new towing-drivers.

The towing computer in your Porsche is great, I'm sure, but it can't teach you basic physics or ensure that your trailer is mechanically sound.

I really wish the DMV would require people to learn this stuff before attaching a trailer to their vehicle.

If you see a gray Model Y with a family of five in it, that's me.

... And the next time I see a Cayenne towing something, I'm going to think of you, and I'm going to maintain a following distance of about a quarter-mile...

 

[PilotPete]

You can't see the action on the drum brake? Usually you can see the clamp from the back (axle) side unless they're fully enclosed... You could place a pressure or piezo sensor on the brake line to detect the action.

-Crissa

I vote that Neo drills a hole and installs a small camera and lights inside the drum to observe the braking action, along with compressed air to clear the camera. The shots should look like the internal O2 tank cameras at SpaceX.
Shy of this, a series of pressure sensors and relays and some servos and maybe a few transducers to give a read out.

 

[COLAB]

I use this device for different trail for eletric breacks :

https://www.amazon.ca/-/fr/51180-Ec...ocphy=1002661&hvtargid=pla-584363310600&psc=1

Works well and esay to set ! ?