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Speed signs not detected by Teslas?

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I've only had my Model Y a couple of days, but today I got to drive extensively on a range of different roads. The biggest surprise to me is that Tesla's (or mine anyway) do not detect speed signs. My last couple of cars have both had this ability, so it surprised me that Tesla's seem to use map data only, which is quite unreliable. Do I have a fault?

Also on narrower B-roads and using plain traffic aware cruise control, when the road bends to the left and a car is oncoming, the Tesla seems to expect a crash, alarms blare out and it brakes hard. The aptly named phantom braking. Again, something my past cars have handled very well. I will try turning off the collision detection, but surely Teslas are better than this?

Am I doing something wrong, have a dud, or are Teslas lagging in these areas?
 
I will try turning off the collision detection

You may have it set to "Early" (or something like that), which is very / over aggressive. I very occasionally get "corrective steering" alert on narrow country roads, but that is without any oncoming traffic, just the narrowness of the road / markings / verge / whatever looking like a possible threat. (I live in a rural area of narrow roads, so even given that "it aint often" in my case)

My last couple of cars have both had this ability

Curious to know what they are, as I thought that was somewhat uncommon - perhaps they were high-end models?

As far as I know it is database only (my car with FSD seems to be accurate, but maybe the database for speed limits around here has good quality data)

've only had my Model Y a couple of days

There is a slim chance that your car has stale map data (almost certainly it will have stale system software, if so that will update, potentially multiple times, over the coming days - parking the car where it has WiFi will help with that) - that won't get you sign-reading! but it might get you a more recent version of the map data.

I am reasonably sure that mine (FSD) recognised temporary speed limits (road works type ones) at some point, but it certainly doesn't at present, so either my faulty memory, or an update that shouldn't-have-been [e.g. not approved for UK] and was subsequently removed.

I expect it is entirely possible that will be fixed by OTA update at some point in your ownership (although quite possibly only if you have EAP or FSD). No consolation, but probably some feel-good if and when it happens
 
My M3 does. Lot of temporary 20 zones where they don't bother putting normal speed limit recommencement signs so the car whines they I’m doing 40mph until it sees a repeater.

Plus “play streets” where the local youth like to rotate the signs 😂
 
I set my cruise control (one press down on right stalk) to do current vehicle speed rather than roadsign speeds. Then right scroll wheel up or down to adjust. fast spin 5mph, slow 1mph adjustments
That’s what I do. EAP is pretty much pointless, right now, for me. It doesn’t make driving less stressful/easy as it doesn’t slow for changes in speed limits/temp road signs.
 
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The aptly named phantom braking.

I’m sure the phantom braking is when your cruising along and it brakes with no warnings and for no apparent reason. That happens to me now and then, typically when passing a lorry - the graphic jumps about so I assume it gets confused. However, braking wouldn’t prevent a collision if that was the case. Most of the time it could have swerved to the right. It can be annoying for people behind when it brakes hard from 70 to 50! I barely use adaptive cruise control due to this.

I turned the alert systems off/down as they couldn’t cope with winding country roads. Every on coming vehicle is considered a weapon!
 
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How you finding the car @Lee Davis ?
Liking the smooth power delivery.
My wife thought she’d be able to cope with the harshness of the ride, but it’s proving a deal breaker. We’re having a long run out today, so we’ll see.
Liking the fancy iPad screen
Liking the remote connectivity
Finding the driving technology underwhelming. This has been the biggest surprise.
Overall, its Ok. Pleased to be in an EV, but ride might break the deal and my wife’s back.
 
Liking the smooth power delivery.
My wife thought she’d be able to cope with the harshness of the ride, but it’s proving a deal breaker. We’re having a long run out today, so we’ll see.
Liking the fancy iPad screen
Liking the remote connectivity
Finding the driving technology underwhelming. This has been the biggest surprise.
Overall, its Ok. Pleased to be in an EV, but ride might break the deal and my wife’s back.
The suspension thing really is strange. Some people report it as harsh and others don't, I've heard reports or them forgetting to take something from between the coils so maybe get that checked? As mine is absolutely fine