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Cruise Control Setting Issue

Cruise Control Setting Issue

How may one engage the cruise control at the speed at which one is presently driving instead of the vehicle's detected maximum? I can find no way. Engaging cruise is often a very jerky and scary experience when the detected speed is wrong (often), or when in a construction zone (for example).

If there is no way, we have a little problem.

casun | September 23, 2018

do you have eap? page 61 of the manual says to press down once on the right gear lever and release it.

Jiver | September 23, 2018

Page 61 says "the number shown in gray is determined by Speed Assist". This sends you to page 82. From there, you have instructions to turn speed assist off. I actually have the same issue as the OP and I have not turned off speed assist to try that out because I like the function overall.

What works for me is only engaging TACC when I am behind another vehicle so that I do not accelerate in a jerky way or I make sure that I am traveling at a the speed that is already in the gray circle. Otherwise I know that I will have to engage TACC and immediately start rolling the right wheel down to get the speed to where I really want it. I realize that these are kludges. I have my TACC set to go to the speed limit without an offset because of this behavior as well.

wiboater4 | September 23, 2018

Jiver has it right. Keep in mind it's the GPS data that is giving the car the wrong speed limit. GPS is not up to date on recent speed limit changes on some roads near me. That is not a defect in the car. You'll get used to using the cruise control as you use it more.

EVRider | September 23, 2018

The manual has conflicting information about this. If you’re already exceeding the speed limit (plus any offset), enabling TACC will use your current speed; if you’re going slower than limit + offset, I believe TACC will use the higher speed.

sduck409 | September 23, 2018

This is a bug. I've reported it to tesla, and I encourage everyone else to do so also - use the Ask A Question form on your account>manage page. Oh, and follow up if they say it's working just fine, RTFM, as they did with me - perhaps I had worded my original email poorly, but they got it the second time.

If you have EAP (don't know about non-EAP cars) once the car has determined the speed limit for a road that you are driving on, and is displaying it in that little speed limit box to the top right of the driver information section, when you engage TACC it'll set to the speed you are going if you are at or over that speed limit, but if you are going slower, it won't set at the speed you are going, but at that displayed speed. There are no settings options in the autopilot section that change this.

This is a pretty serious safety related bug - it could potentially cause unintended acceleration with someone who wasn't aware of it. There's a road near me that is signed as a 40 MPH speed limit area, but there is a long stretch of school zone that is 20 MPH when school is letting in or out; it would be nice to just flip the lever and have it stay at 20. But currently you have to do some serious spinning of the right knob to get it set correctly after flipping the stalk.

gmr6415 | September 23, 2018

Do you have your speed limit warning set or have you set it and turned it off leaving a number other than zero in "offset"?

If you have it set at say 8 mph over the speed limit in "offset" when you engage cruise control it will jump up to that offset over the speed you are driving at. Even if you have a speed limit warning set there and have turned off the warning it will still jump up to the given speed speed you are driving at plus whatever the offset is set at.

Got to settings > autopilot> hit the settings "gear" in the upper right hand corner is see if there is anything other than zero in the "offset" setting. If so turn the warning on, set the offset to zero, then turn it off. Your troubles should go away.

Whdame | September 23, 2018

+1 for (gmr6415 ).....this is what I was going to post. It was a learning curve. The offset "relative or absolute" is what you are talking about. If you use the offset and then use cruise it will go to the "offset" number and speed up like the car feels it is getting away from you.

sduck409 | September 23, 2018

@gmr6415 @Whdame this is somewhat correct, but not what I or the OP were talking about. The settings speed limit warning have no effect with this issue. I've read the manual, and done extensive testing of the various different settings available there, and they don't apply here. The issue is trying to set TACC to the speed you are driving - If the car has decided that the speed limit is 40 MPH for instance, and you are driving 30 MPH, when you engage TACC it'll set it to 40 MPH, no matter what the settings are in the speed limit warning section. Try it and see! There should be a way to set TACC to engage at the speed you are driving, but there currently isn't if you are going below the speed limit determined by the car.

Whdame | September 23, 2018

@sduck409 - Now I am lost because I did it tonight. If it is selected to "absolute" and I am doing 40mph in a 50mph zone and turn on TACC the car stays at 40mph.

Am I missing something? I am kind of old and 2.5 beers in now that I am home....but?

Whdame | September 23, 2018

@sduck409 - I will check it again tomorrow because as someone mentioned about the speeds are GPS driven as the car is not reading the signs as of yet. When I did the test tonight, I saw the road sign at 50mph and dropped my speed down to 40mph with no cars in front of me to tag onto. What I just realized is I did NOT remember looking at the little sign on the screen to see if the car thought it was a 40 or 50mph zone. (my fault) I will retest in the morning.

The speed could have been 40mph a while ago on that road and they up'd the speed to 50mph and the car still thinks it was 40 for TACC worked as I said.

sduck409 | September 23, 2018

@Whdame what matters is what the car is displaying as the speed limit. Not what the signs IRL say. But please experiment further tomorrow! I spent a whole morning trying to get it to work properly, and the only times it would work setting the TACC speed lower than the speed limit was when the car wasn't displaying a speed limit - apparently not all roads are registered in the GPS database for speeds, and of course they all aren't updated automatically.

What's important is that tesla has acknowledged that this is a bug, so hopefully it'll get fixed.

ralyrcr | November 7, 2018

I'm also very bothered by this problem. My 70 year old father who drives the car responds in a very dangerous way the car lurches ahead on him. When will they fix this issue. On the model S it's so easy because of the independent cruise control stalk. I'm very frustrated by this, any word on what's Happening?

ralyrcr | November 7, 2018

I'm also very bothered by this problem. My 70 year old father who drives the car responds in a very dangerous way the car lurches ahead on him. When will they fix this issue. On the model S it's so easy because of the independent cruise control stalk. I'm very frustrated by this, any word on what's Happening?

ralyrcr | November 7, 2018

I'm also very bothered by this problem. My 70 year old father who drives the car responds in a very dangerous way the car lurches ahead on him. When will they fix this issue. On the model S it's so easy because of the independent cruise control stalk. I'm very frustrated by this, any word on what's Happening?

dgknox | November 26, 2018

This darn near wrecked me today as -
a) I just got my Model X on Saturday so I'm still "new"
b) we received 6" of snow in Michigan last night
c) traffic moving 35-40mph on 70mph interstate
d) setting cruise control (TACC right?)and the car starts fishtailing as it accelerates to 70 on ice...nearly slid off the road

I couldn't fix the TACC on the drive here, didn't want to try that hard to "experiment" on ice...

andy.connor.e | November 26, 2018

First question is, what are u doing setting cruise control in snowy/icy conditions?

Bighorn | November 26, 2018

@andy
Excellent point. Not everyone knows. Regional states have digital billboards reminding people to turn off cruise control when the weather is bad.
I do agree that the current set up is bad, though, where cruise control has a predetermined set point.

Sorry Charlie | March 19, 2019

Just updated to 2k AP on my M3 . Test driving TAAC I found it to be very jerky, especially when it slows down to maintain car lengths.. braking like someone with a he heavy foot on pedal, not gradual or very pleasant.
Anyone with the same experience?

cascadiadesign | March 19, 2019

100% agree - This is not the way TACC should work.

First, I use my +5 MPH Relative Offset as a warning chime. It doesn't mean I want to consistently drive 5 over the limit. It means I want to be aware when I stray 5 over. So why does TACC assume I want to cruise 5 over by default???

Second, It would make for a smoother, and less jarring transition to assume the driver wants to stay at the speed at which TACC was engaged. It's easier to scroll up the speed than to have TACC suddenly accelerate, forcing the driver to scroll down quickly.

In summary, it's wrong for TACC to assume the speed limit (or speed limit + Offset) is the safe, or desired speed, at the moment it is engaged. If the car is going below the posted speed limit, it's better to assume the driver is going at a safe speed when they engage, and the driver will scroll up to a cruising speed when safe to do so.

cascadiadesign | March 19, 2019

@rick - I have the same issue. It feels like the car is waiting too long to begin slowing, then brakes harder than it would need to otherwise. Not comfortable for me either.

RES IPSA | March 19, 2019

TACC is best at slow bumper to bumper traffic or normal to high speeds with light traffic.

It is least effective when traffic is heavy yet moving along at 60-80 mph

sjm4660 | March 19, 2019

Yes I got it last week also. TACC is unusable when there is a vehicle to follow because of constant acceleration/deceleration. My passengers get nauseous after a couple of minutes. This can't be 'normal' otherwise everyone would be complaining about it. I'm still hoping that the sensors will calibrate themselves somehow.

Reflex | March 19, 2019

Well, this is great to read after (reluctantly) spending $2k on AP. (sarcasm)

RES IPSA | March 19, 2019

AP is still very useful and a great deal at 2k... just isn't perfect in all highway driving conditions

Jiver | March 20, 2019

When I posted back in September of 2018 I had only had my car a few weeks. I've now grown accustomed to how TACC works and I have even learned to like it -- mostly. I like that I can start accelerating from a stop sign and engage TACC at 18 mph and have it continue to accelerate the car up to the speed limit. That behavior works for me very well where I do most of my driving.

Unfortunately, 2019.5.15 seems to be a step backwards in TACC. Braking is more severe as others have pointed out. Acceleration does not seem to be as quick. Follow distances are farther. Even at "1" you now have more than a car length between you and car in front of you in stopped traffic. In most instances where I drive that is too much (I used to drive on "3" all of the time). Slowdowns when going around corners are now so severe that I can no longer use TACC on many roads were I used to use it every day. While these things are annoying to me now, I really think that they will be improved in a future release as I already know that they can be better (in my opinion anyway) because they were better.

On a completely unrelated note, my automatic high beams now work quite well. I had not used them for months because they were so bad but finally decided to give them a go again with 5.15. My automatic windshield wipers also appear to be greatly improved although the sample size is small. Again, I have not had that turned on in some time but with 5.15 decided to check it out again. Things do get improved.

jeff d | March 20, 2019

I actually had a positive TACC experience today, BTW what software you all on, I'm on 2018.50.something.

I test the CC under different situations so I understand how it will react. Today open road in front of me, on a two lane off ramp. My CC speed was set at 70 (that's the speed limit but isn't reclassified on the off ramp which I blame DOT for). I engaged AP as I was on the straight way approaching the off ramp... set speed 70, AP engaged, speed 54 mph which may or may not be above the safe speed for the exit (it's highway to highway exchanges, so 55 may be fine). In any case I was pleasantly surprised that the car didn't accelerate into the turn at 70.

My biggest issues with CC are:
1) the shift stalk is the same as my wipers on my fusion, I keep accidently turning on CC when trying to clear the water...
2) I don't like the only way to disengaging CC when disengaging AP is to use the stalk or brakes. I've found many times I have to turn the wheel because the AP can't change lanes. Next thing you know is the car sees an opening and accelerates because I changed lanes. I don't press the brake when driving because it's stupid to brake for no reason. Too often that causes ripple of brake lights which leads to a massive slow down that devolves into a traffic jam. All cuz someone tapped their brake for a split second...

Thrillion | March 21, 2019

I did notice TACC accel and decel more recently with 5.15 on my 200 mile trip times two.
I assumed it was the vehicle I was folllowing not on using their cruise control and therefore speeding up when they noticed a drop in speed.
AP worked well except on the way home there are highway exits on the left, AP thought the lane was widening which then tried to center in that widen lane only to jerk back in the correct lane once it saw the dashed lines.
The exit dashed lines should extend from the beginning of the exit, not start once there is room for two lanes.
I can't change the roads.
It didn't help that the vehicle in front of me road ON the lane line and AP could recognize the line until the line passed under the car. I resolved the problem by backing off the vehicle in front to give AP time to see the lane lines.

Stefan14 | April 11, 2019

Model 3, 2019.8.4

100% agree with cascadiadesign

>> In summary, it's wrong for TACC to assume the speed limit (or speed limit + Offset) is the safe, or desired speed, at the moment it is engaged. If the car is going below the posted speed limit, it's better to assume the driver is going at a safe speed when they engage, and the driver will scroll up to a cruising speed when safe to do so.

Anyone from Tesla in this forum who can provide answers? Does anyone know if this is a bug or feature? :-)

Carl Thompson | April 11, 2019

@cascadiadesign, @Stefan14

"... it's wrong for TACC to assume the speed limit (or speed limit + Offset) is the safe, or desired speed, at the moment it is engaged."

Completely agree.

RedPillSucks | April 11, 2019

@sduck409 et. al.
It's not a bug, per se, in that it seems to be working as designed and documented.
Having said that, I also agree that it really should use the current speed instead of the max speed.
I think it's completely appropriate to file a bug report and mention how you think it should work.
Tesla has shown that its responsive to these types of changes, so ...

don.lind | April 11, 2019

I have the plain old non-TACC cruise control. I engage it and it uses my current speed. Good and expected.

Even if TACC is "designed" to accelerate to the "posted" speed limit when engaged, that's crazy and wrong.

As a software guy, designs are sometimes wrong... and designs (and the associated code) need to be fixed when reality sets in. :-) This sounds like a bug to me.

greg2011 | August 10, 2019

The majority of owners seems to dislike the current "set to speed limit" behavior, and prefer "set to current speed" instead. But how do we get this?

Right now, we have to start scrolling down until we reach the desired/current speed.
Would you agree the first scroll should immediately jump to "current speed"?

FISHEV | August 11, 2019

I’d agree on it setting to current speed. That’s the intent when setting cruise. Adding more eyes off the road to see what the speed setting is and then spin dial and see what the new speed setting is not good.

greg2011 | August 12, 2019

Okay, what do we have to do to get this? Twitter to Elon, Tesla etc.?

msmith55 | August 12, 2019

What is needed is the ability to set a new speed limit to update the GPS mapped speed limit, to correct the mapped speed limit.

majassow | August 12, 2019

I disagree with setting to the current speed. That thinking works only for old school cruise control. I often will engage TACC in stop and go traffic, and it would be annoying to have to adjust up to the current speed limit. Had to do this with my old ACC, and found it annoying.

jstat10 | August 12, 2019

My Owner's Manual says

"This sets the cruising speed to the detected speed limit (plus any offset you've specified using Speed Assist as described in Controlling Speed Assist on page 93) or your current driving speed, whichever is greater."

So if you are driving fast enough, it will set the cruising speed to the current speed. Works for me. I have speed limit set to absolute, not relative. I think if you set "relative" speed to something like -20 you would get the desired(?) behavior of setting it to the current speed that is less than the speed limit.

FISHEV | August 12, 2019

I think default is it sets to whatever your current speed is, the "Absolute" setting. "Relative" setting would be speed limit and some set percentage of the speed limit.

Setting to car's current speed seems the most intuitive, driver is engaging at speed he wants to travel. Works on highway or on surface street stop and go.

MrSexyTime | August 12, 2019

Personal findings: grey is current speed up to a point. Left hand turn into private road (no speed limit known to Google), uses last known speed (59mph though I'm in a private 22). Right hand turn into private road uses logic (grey comes at 18 and flows with current speed). Note. When I make my left and got 59, making a subsequent right onto another private road does not change from 59 to a logical speed. (28.2).

majassow | August 12, 2019

@jstat10: if it does work like that (and logic says it should) then the option to set to the current speed would already be supported. A bit unintuitive, but worth a try for those that insist the current logic is wrong.

philippem | August 12, 2019

I think that a good compromise would be to not accelerate while the stalk is depressed and if the stack is depressed more than a second or so, set the speed at the current speed when the stalk is released (that way you can adjust the speed a bit if desired).

If the stack is release rapidly (within about a second), then use maximum speed between current speed and speed limit. No offset should be applied of the offset should be independent of the alarm speed.

Speaking of alarm speed warning, it would be nice to reduce them when the TACC speed is set at or above the alarm set limit and TACC speed variation make it cross that limit multiple time.