When, specifically, are hills held when hill holder is ON?

[jerry33]

It seems to differ from car to car. I had a loaner and one of the things I noticed was hill hold engaging on much lighter slopes compared to my car.

The loaner I had two days ago (annual service, no actual problems) didn't seem any different in that regard, however, I did notice that the brakes were much more sensitive than in my car. It was hard to stop smoothly, although by the end of the second day I was adapting.

 

[scottm]

Well, based in feedback here, the feature is a bit iffy... it's a sometimes feature. And maybe depends on car variances. So get to know when yours works and when it doesn't and adjust individual expectations accordingly. It's only a convenience feature anyway, as I say not critical.

in my case I never expect it to work because I can't know when it might.. and I don't drive a very hilly route so it is not enough of an annoyance to me.

Those in SF bay area might have a different say, and depend on things like this more because their hills are steep.
I would probably resort to the 2 foot driving of any other car on steep hills, left foot on brake, release it as gas pedal gets pressed and tranny spins enough to hold car in place on an upward hill. Even in my Tesla, because I dont know if hill holder would work ... when there is guy close on your rear on a hill.. I hate those roll back situations.

I have found that pressing both pedals on the S gives a popup message saying both pedals are pressed. And is the hint that if you are going nowhere and pressing hard on the accel pedal... check your other foot and get it off the brake. Which, of course, is the human edition of hill holder feature.

Makes it hard to do a brake stand with the S! But I guess with all that power on demand and a traction OFF button is all we need for a smoke show, dont need to pre-rev the piss out of the ICE to find its torque.:wink:

 

[Cyclone]

I don't think this will be a problem for me given the areas I travel, but I have to say I like very much how my 4Runner does it. Once I engage the brake on a hill and let go, it continues to hold the brake until I hit the gas. I have tried it out and can even remain stationary for 30 seconds (didn't try longer). Even the slightest tap on the gas (not even enough to "creep" forward on the hill), and it disengages and I can roll back. Thankfully, the creep of my automatic transmission will hold me on most hills around here even in that case. But it has come handy a few times as I let off the brake when the light turns green only to find the person in front of me hasn't finished texting!

 

[scottm]

That's the other thing I could try, creep mode on. That might be enough "pull" when I take foot off brake maybe creep will hold the car on a hill to keep from rolling back. Or maybe even creep it forward uphill.

 

[jcaspar]

Mine works on steep grades but not always on mild grades which is fine because it is unnecessary on little hills.

 

[mknox]

Tesla's hill assist should extend to all situations when the car is stopped, even on flat terrain. The "hill assist" should hold the car indefinitely until you press on the accelerator pedal. This way it will always work.

Agree. And for those who don't want or like it, just make "Hill Assist" a toggle similar to how you can turn "Creep" on or off.

 

[AmpedRealtor]

Cannot edit posts, therefore an UPDATE:

Hill assist works on every terrain, all the time, but just for 1-2 seconds, not indefinitely.

Cheers

Frank

Sent from my phone using Forum Fiend.

Are you sure? It doesn't work on my driveway or the freeway offramp to my house. The inclines are not steep enough and the car rolls back. It does not work on every terrain, but it should.

- - - Updated - - -

The loaner I had two days ago (annual service, no actual problems) didn't seem any different in that regard, however, I did notice that the brakes were much more sensitive than in my car. It was hard to stop smoothly, although by the end of the second day I was adapting.

You drove one of the new autopilot cars with the electromechanical braking system. I also don't like how sensitive those brakes are, but that can likely be changed in software.

 

[ken830]

I think it works great the way it does. Steeper hills, it engages. All other times, it doesn't. You definitely don't want it to engage in all situations/grades -- like if you are in "D" and pointed downhill, or in "R" and pointed uphill. I also like the feeling of "neutral" on mostly-flat terrains. Feels like a manual transmission car that I'm used to. Hill hold is great only on steep hills.

 

[billarnett]

...the feature is a bit iffy...

I totally don't get this feature. Why not just use your left foot on the brake? There's no clutch to worry about after all . That's what I always do in my Roadster (and my Jeep).

 

[mknox]

I totally don't get this feature. Why not just use your left foot on the brake? There's no clutch to worry about after all . That's what I always do in my Roadster (and my Jeep).

I agree, and made this point myself some time ago. Same number of pedals as legs, so what's the big deal? Having said that, since they've implemented it there are probably tweaks that could make it better.

 

[ecarfan]

Many cars have a hill hold feature. Many people really like it. Some don't. There are lengthy topics discussing it.

 

[mknox]

Many cars have a hill hold feature. Many people really like it. Some don't. There are lengthy topics discussing it.

I'm kinda neutral on it. It does seem odd that it isn't switchable like "Creep" is.

I find that when it works, it works great, but unfortunately about 75% of my situations are on gradual inclines where the car still noticeably rolls back and it doesn't engage. I just wonder why it doesn't work every time you stop. What difference would it make if the ground was level? The car doesn't move anyway until you press the accelerator so what's the difference? That way it would work on every type of incline, every time.

 

[AmpedRealtor]

I sent an email to Tesla about how this feature works, here is what they said:

Hello Mr. [AmpedRealtor],

Thank you for contacting Tesla Motors Technical Support regarding your question about Hill Start Assist. This feature, which was introduced in firmware version 5.9, is intended to automatically hold the car by maintaining brake pressure when the brake pedal is released, preventing the car from rolling while the driver switches form the brake to the accelerator. Hill Start Assist will release after one second, or when the vehicle begins to accelerate. This function will engage when the car is in Drive and facing uphill, or in Reverse and facing downhill. It is always enabled when the vehicle is in Drive or Reverse and does not need to be activated by the user. The feature engages on grades of more than 4% incline/decline.

I’m not aware, nor was I able to find any information regarding how firmly the brake needs to be depressed in order to engage Hill Start Assist. I would be led to believe that the intention would be for the feature to engage whenever the brake is held, no matter the pressure. If you believe the feature is not working properly and/or would like to have a service technician “test ride” the car to see for themselves, we’d be happy to arrange for that with your local service center.

Feel free to let us know if you have any additional questions.

Best regards,
Eric

 

[billarnett]

... The feature engages on grades of more than 4% incline/decline...

Ah. Perhaps that's the rub. A 4% grade is actually much steeper than most people would estimate. It's entirely possible that all the instances where Hill Start Assist is failing are ones where the grade is less than that but still enough to let the car roll downhill.

 

[jerry33]

Ah. Perhaps that's the rub. A 4% grade is actually much steeper than most people would estimate.

To put this in perspective, 4% is the maximum grade a subway with steel wheels can negotiate.

 

[bxr140]

I'm pretty sure it has something to do with the pedal pressure with which you hold your position. Notionally, at a flat stop you don't put much pressure on the pedal to remain stationary...but to do so on an inclide you need to press harder.

 

[mknox]

I'm pretty sure it has something to do with the pedal pressure with which you hold your position. Notionally, at a flat stop you don't put much pressure on the pedal to remain stationary...but to do so on an inclide you need to press harder.

I don't think so. I've tried standing on the brake at those slight inclines where hill holder doesn't come on to see if that is true, but my car will still roll back.

 

[bxr140]

I don't think so. I've tried standing on the brake at those slight inclines where hill holder doesn't come on to see if that is true, but my car will still roll back.

There may also be a time element. It may be a false positive, but i can always get hill assist to kick in with sustained pressure.

 

[AmpedRealtor]

I'm pretty sure it has something to do with the pedal pressure with which you hold your position. Notionally, at a flat stop you don't put much pressure on the pedal to remain stationary...but to do so on an inclide you need to press harder.

Please see response from Tesla which I already posted. Has nothing to do with pedal pressure.

 

[gregincal]

My experience has been that it never holds on minor grades. That said, the feature works just fine for me. If the grade is shallow enough that hill hold doesn't engage the car might roll back maybe an inch before I accelerate forward with a normal (not hurried) switch of my foot to the accelerator. Any hill where roll-back is a concern Hill Assist engages.