Autopilot question

[MacJester]

Hi,

I took delivery of my M3 on Friday, and have been enjoying playing with autopilot. I am a bit puzzled by something though. It’s broadly fine at dropping the speed when the speed limit changes down, but doesn’t increase the max speed when it moves back up again (eg 60 down to 40 is ok, but a follow on increase back to 60 doesn’t change what the car is doing). Is there a way to get the speed limit to adjust back up without turning autopilot off and on again?

 

[Mr Miserable]

Press the speed limit icon.

 

[NorfolkMustard]

You can tap the speed limit sign on the screen

 

[MrBadger]

I am a bit puzzled by something though. It’s broadly fine at dropping the speed when the speed limit changes down, but doesn’t increase the max speed when it moves back up again (eg 60 down to 40 is ok, but a follow on increase back to 60 doesn’t change what the car is doing)

I'm also puzzled.

Short of slowing down when car in front does to maintain gap, or slowing for some corners (and not for others, do you feel lucky punk...), the car is not speed limit aware so will not slow down based on speed limits. The only time it is speed limit aware, is when turning on TACC/AP.

Are you seeing different behaviour?

 

[NorfolkMustard]

I've had it do that too - it seems to happen on country lanes it's perhaps not familiar with - it comes up with a warning saying "autosteer limited to <speedlimit + offset>"

I had it reduce my speed from 60 to 40 automatically when the speed limit changed.

 

[Mr Miserable]

From the manual: TACC Page 90

Warning: When cruising at the speed limit, the cruising speed does not change when the speed limit changes. If your driving speed is at or below the new speed limit, move the lever up to cancel Traffic-Aware Cruise Control, then move it back down again to re-initiate and cruise at the new speed limit. You can also manually adjust your cruising speed (see Changing the Set Speed on page 91).

The manual doesn't mention tapping the speed limit sign on the screen but, trust us, it does work.

 

[MacJester]

I'm also puzzled.

Short of slowing down when car in front does to maintain gap, or slowing for some corners (and not for others, do you feel lucky punk...), the car is not speed limit aware so will not slow down based on speed limits. The only time it is speed limit aware, is when turning on TACC/AP.

Are you seeing different behaviour?

Yes. It seems fine with slowing down when it goes into a lower speed limit. In fairness I got the FSD computer, and perhaps that makes a difference?

 

[MrBadger]

I have FSD. Never had it slow down except when following a car that also slowed down. I would be careful, sounds like you think its doing something which it does not yet do. Unless you have later firmware but I've not seen it mentioned in that.

It will slow down for some things, sometimes, like corners, maybe roundabouts if you are lucky. But not speed limits.

 

[BZM3]

I have FSD. Never had it slow down except when following a car that also slowed down. I would be careful, sounds like you think its doing something which it does not yet do. Unless you have later firmware but I've not seen it mentioned in that.

It will slow down for some things, sometimes, like corners, maybe roundabouts if you are lucky. But not speed limits.

wrong....

 

[MrBadger]

wrong....

​

Well they must all be fake speed limit signs then cos mine doesn't slow for them.

Where does yours slow down?

 

[BZM3]

​

Well they must all be fake speed limit signs then cos mine doesn't slow for them.

Where does yours slow down?

If the navigation has the speed limit data for the road you are traveling on (tied to GPS), it will automatically adhere to the speed limit while on AP by reducing the speed if it changes. The speed limit is visible on your display opposite the AP steering wheel icon.

You may have accidentally disabled the setting in the cars options.

 

[MrBadger]

Ill have a check, but can never remember ever having had the car slow down for a speed limit other than when following another car.

The only evidence I see of car being speed limit aware, other than when engaging TACC, is when my speed limit sign changes in size if I am exceeding the speed limit.

 

[NorfolkMustard]

If the navigation has the speed limit data for the road you are traveling on (tied to GPS), it will automatically adhere to the speed limit while on AP by reducing the speed if it changes. The speed limit is visible on your display opposite the AP steering wheel icon.

You may have accidentally disabled the setting in the cars options.

Perhaps it does that on an AP1 car - what car do you have?

on the Model3, it will only change speed to stick to a changed speedlimit if autosteer is enabled AND this specific situation referred to on page 96 occurs. In normal driving, without this special situation, the model 3 will not automatically adjust its speed in line with speedlimit signs or GPS/map knowledge.

--
Restricted Speed
Autosteer is intended for use only by a fully attentive driver on freeways and highways where access is limited by entry and exit ramps. If you choose to use Autosteer on residential roads, a road without a center divider, or a road where access is not limited, Autosteer may limit the maximum allowed cruising speed and the touchscreen displays a message indicating that speed is restricted. The restricted speed can vary depending on whether or not you've specified a speed limit offset. Although you will be unable to increase the cruising speed, you can select a more restrictive cruising speed by reducing the speed limit offset, if applicable, (see Controlling Speed Assist on page 112) or by manually reducing the set cruising speed (see Changing the Set Speed on page 91).

--

I had this happen to me yesterday on a NSL country lane when the speedlimit changed to 40. The "Autosteer is limited to 63mph" came up first, and then when the speed limit changed to 40, the car's target speed also reduced to 43mph (my offset is +3mph) without my intervention

 

[Mr Miserable]

From the manual: TACC Page 90

Warning: When cruising at the speed limit, the cruising speed does not change when the speed limit changes. .

This is from the Model 3 manual. My experience agrees with the manual.

 

[MrBadger]

3:40 - sadly skip to timestamp got lost by forum link

Also 8:11 only slowed down due to van in front

Maybe I'm just slowing the car so it is at correct speed limit when it enters the speed limit rather than waiting until after the speed limit.

 

[MrBadger]

And I thought I was going slightly mad. Phew...

 

[NorfolkMustard]

The manual doesn't mention tapping the speed limit sign on the screen but, trust us, it does work.

It's mentioned briefly at the top of page 112 in the EU manual

 

[Mr Miserable]

It's mentioned briefly at the top of page 112 in the EU manual

You're spot on.

 

[WannabeOwner]

the car is not speed limit aware

GPS database [AP2+ rather than AP1] for speed signs (not perfectly accurate, but ...

Speed Sign Icon, on dashboard, should change when you pass the sign (well .. when the GPS database-location is reached)

Doesn't help with gantry / roadworks signs, until they are in a national database (or Tesla decides to have speed sign recognition as per MobileEye)

 

[MrBadger]

Without taking the quote out of context, AP2+ does not react to speed limits (except restricted limits above) except when turning on TACC/AP, hitting the speed sign icon when in TACC/AP or showing the GPS speed limit on display and/or gives a speeding warning.