@SDKoala is correct IMO.
In Short: I think this is an issue and one that may wind up on the front of the next 'Let's short Tesla' headline. It is a Model 3 only problem, S/X & Roadster don't suffer this issue.
At length, I've been nagging Tesla since the first time I activated cruise control at 25mph in a school zone and was suddenly launched forwards by the car! It won't hit anything, as it's distance aware so, this isn't a big safety concern but, for me, I'm finding that I can't use cruise control very much at all and I want a refund.
I've spoken to Tesla and been surprisingly misunderstood. It seems that the whole interface is misleading as they seem to have inadvertently co-mingled
speed warning and
cruise control onto the same set of UI controls:
- Speed warning is a feature to help avoid unintended speeding, basically, to avoid a ticket.
- Cruise control is a feature to maintain vehicle speed automatically.
These are not connected however, in Tesla parlance they seem to have inadvertently become one. I think that everyone at Tesla is misunderstanding my complaint/fear* because of this connection.
One proposal I received from Tesla was a solution where the speed warning buffer would be updated to allow a negative value.
Below I’ve laid out the concern, and a simple fix. I’ve also outlined why the current proposed fix will
not work.
Example failure scenario
- My local school is on a 40mph road. During school hours the speed is 25mph whilst lights are flashing. There is a long downhill followed by a long uphill. I can’t use cruse control in this scenario as the car accelerates to 40mph regardless of the time of day.
- Traveling on the NJ Parkway I hit long stretches of roadworks with speed limit of 45mph. I can’t use cruse control at this time as the car accelerates to the assumed limit of 65mph.
- I want to have speed warning set at 5mph above the posted signs. If I do this, I can’t use cruise control at the posted limit, instead that car accelerates to the posted limit PLUS the speed warning margin.
- I’m driving on a 35mph road at 35mph however, the car is mis-categorizing the post speed limit as 45mph. I cannot use the cruise control as the car accelerates to 10mph over the posted limit (more if the extra 5mph buffer were included!) (please don’t ask where this occurs, fixing the GPS database is not the issue at hand here
The simple ask
I can’t set my cruise control to the current road speed because the car instead, accelerates violently to what it believes is the maximum posted speed I should be driving at.
This is clearly wrong, if you read what I’m saying, the absurdity should become clear.
The simple fix
- Enable the ‘set’ function on the cruise control to set at the current road speed.
Why the current proposed fix won’t work
The proposed fix of allowing a ‘negative’ speed warning offset will result in the speed warning chime sounding every time you cross the threshold. For example:
- I set the offset to -5mph. The warning chimes every time I hit 35mph on a road with a posted speed limit of 40mph.
- I set the offset to -5mph. When driving in a school zone on a road that has a 40mph posted limit, setting the cruise control results in the car accelerating to 35mph.
- I set the offset to -20mph to ensure I can set the speed to 25mph in a 40mph zone. The warning chimes nearly every time I get out of my driveway.
If anyone has any ideas on how we can get this fixed, I'm all ears!
**My fear is that this phenomenon will be branded as ‘
unintended acceleration’ which always has the media in a fizz. Now is not the time for more crazy press! I’ve managed enough ‘
situations’ with Tesla during the early years running Tesla Motors Club, when I’d get a call from Rachel Konrad or even Colette Niazmand because of some stupid comment (Now known as 'fake news') about a Tesla fire or some accident that proved electric cars where dangerous, so I know how quickly mis-information can be twisted and this feels like just that kind of thing.