Does ACC allow fully automatic speed limit observance ?

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Rod Speed
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Post by Rod Speed »

Does the traffic sign capture and ACC allow completely automatic following of the speed limit when you are driving along the highway with ACC on and you come to a town with a lower speed limit so that it slows down thru the town automatically and then speeds up again as you leave the town ?

chewystuey
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Post by chewystuey »

I don’t think so.

ACC is adaptive to the car you’re following rather than the speed signs.

I’ve used standard cruise control and it does not change when it reads a different speed sign.
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hdasmith
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Post by hdasmith »

Have you tried switching on the sign adaptive option on the right hand screen on sensus when using ACC? It’s there with the safety options for the speed limiter.

I haven’t used it as it’s not accurate enough with speed limits for my liking. The speed limit sign is useful as a reminder, but very much need to be aware of the limits yourself as it’s not foolproof.
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Rod Speed
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Post by Rod Speed »

I can't try it because I am looking to buy a new car that can do that. My Volvo dealer did claim that it could do that on a phone call but I can't see that the owners manual tells you how to actually set it up to do that. The Volvo dealer is actually 115 miles away so not all that convenient to tell them to set it up in a test drive.
hdasmith
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Post by hdasmith »

Sorry, misunderstood Rod Speed. I know it can do it for the speed limiter, but not sure about cruise control. I do know that the speed limit reader is not very accurate, gets confused by off-ramps and changes in speed on sharp corners or junctions. It also doesn't read all national speed limit signs on smart motorway sign posts.

I also know that if you change the speed of cruise control while driving, it can brake quite hard to get there rather than coasting, so I'm afraid I won't be trying it - too worried someone might get caught out and go into the back of me.

Sorry, that's probably not very helpful.
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libbers
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Post by libbers »

There are two distinct features here, Automatic Speed Limiter (also called Speed Sign Assist) which I think is standard on all xc40s (?), and Adaptive Cruise Control which is part of the Intellisafe Pro package. When ASL is enabled, it actually does nothing until you toggle on the normal Speed Limiter function. I don't have ACC in my car, so don't know if it's possible to combine the two functions, but based on my understanding of how the steering wheel menu works with these driving assist features, I kinda think it might be a case of choosing to drive with one or the other active - not both. Could well be wrong though, someone with Intellisafe Pro will need to confirm.

For what it's worth I gave ASL a test today. It's not a feature I think I'll use much, but for the short distance I tried it worked well and I didn't find the braking too aggressive when I entered a 40 zone from 60.
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Rod Speed
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Post by Rod Speed »

Thanks hdasmith. I dont really mind if its not 100% reliable, because its better to not have to override the ACC for a town or two than have to do that for all towns. And with that highway into a town situation they dont normally put the speed limit sign on a bend anyway, so its likely to see most of them fine.
hdasmith
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Post by hdasmith »

Just another thing to be aware of, after libber’s post, I thought I’d give it a try today. I couldn’t get it to activate for cruise control. It did switch on for the speed limiter, but wasn’t actually doing anything. I realised this was because the maps were updating. It clearly uses the speed info on the satnav to work. Just something to be aware of.
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Rod Speed
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Post by Rod Speed »

Thanks again hdasmith. I don't mind so much where it gets the speed limit data from tho I suppose that getting it from street signs would be better with the lower limits we get when roadworks are happening and in places where the speed limit is varied using traffic volume and accident data. Having to do those manually wouldn't be too bad because they aren't very common at all here with the second approach.
Morten
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Post by Morten »

It dosen’t work for ACC, only speed limiter. I use the speed limiter when driving in cities where I am not known and are foucused on finding my way, I like the function and find the change in speed smooth.

I would like it to work with ACC but that is not the case.

Br Morten
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