OT: Speed limiters on cars

Apr 16, 2022 Last reply: 4 years ago 90 Replies

I see that the Daily Telegraph is reporting that ministers are actively considering speed limiters on new vehicles to fall in line with a similar EU directive.



My Kuga already has such a system and I already have some concerns about how it works. The system relies on a camera spotting road signs rather than GPS, with the limiter on and on the motorway it will pick up the lane speeds from overhead gantry?s and power down the engine to comply but as far as I am aware the brake lights do not come on so no warning to anyone behind.



During normal driving the speed limit displays on the dashboard but the results can be spurious. On a 30mph road I frequently use there a number of side streets which have 20mph limits and on those that are at an acute angle the camera often picks up the road sign and declares the main road limit as 20mph. Partially obscured signs are often missed too.



I can understand the need for safety for considering such systems but to my mind it creates as many problems as it solves.



Richard


That isnt how the EU system works.

Not true of the EU system, the driver is free to override it if he chooses.

Just put something over the camera lens to defocus the image.

No need. It can be turned off. In fact, by default it's off (at least on my Ford S-Max).

Just find a foreign truck with that set of speed limit roundels listed on the back. One of those will reset your speed limit to 90mph.

When entering Oare (on the way to Marlborough) my Suzuki always showed two speed limit signs, one "30" and the other "40", it also misses signs and shows incorrect signs.

I think the EU system relies on GPS.

Surely that is no different to you lifting your foot off the accelerator and allowing your speed to drop? You don't brake, so no brake lights.

Yes, that can be a real problem.

I think that there are also other risks - you pull out to overtake, but the vehicle in front speeds up and the gap you pulled out of has closed up, so you need to accelerate. Even if the system lets you overide it, your planned rate of acceleration has been momentarily interrupted and the overtake takes longer.

Or as I had - a call from the hospital to say that they thought my son had taken a sudden turn for the worse and he might be about to die ... I was not for obeying speed limits on the way back there.

My car will respond to the speed discs on UK trucks, and the speed limit display changes to show if the indicated speed is being complied with or not.

Not in EV mode doing 70mph and the overhead says 50mph the slow down can be quite dramatic

The car does have a kick down on the accelerator to exit limiter mode but as someone has already said that involves a sight delay.

Richard

AFAIK, it's a done deal, I think if you stick your foot down harder it will override it, and maybe beep a little, I'm sure it'll be possible to reprogram it with an OBDII cable ...

Not a great idea where motorways go over or under a dirt track.

My (SEAT Ateca) has a feature where releasing the loud pedal you go into a coast mode which can keep the car at speed for a surprisingly long time. It's all part of the fuel saving gubbins.

Best and most used gadget since 2012 has been the speed limiter in every car I've had since. If people have a problem with it, it's because they are stupid, not because it is in any way new or even complicated.

Weirdly I originally though a cruise control would be a game changer. But not in the UK it seems.

My Jazz Mk3 has a speed limiter, but the software operating it isn't the cleverest.

In "notify" mode, it just displays the speed limit picked up from the signs or motorway gantries. In "limit" mode, it shows the set limit as well as the limit itself, and keeps to that set limit. The set limit can be adjusted up in 1mph steps to a max of 5 mph over the limit. I assume that's to satisfy those who know that car speedos often show speeds higher than the actual speed.

So far so good. The first programming failure is that if you stop the car and turn off the engine, when restarted it does not automatically resume at the same limit, it just resets to an "unknown" limit! Although you can set any limit yourself, if you set it to 40 and you're actually in a 30, you could be in trouble. Why wasn't it programmed to start at the limit set when the engine was stopped?

The second issue is really weird. If you indicate to turn right at, for example, a roundabout or junction, as soon as you begin to straighten out on the new road, the speed indicator resets itself to the "unknown" limit! It does this 9 times out of 10. It's less frequent when turning left, but can occur. Very strangely, it almost never resets if the indicators are not used at the roundabout or junction (am I the only person who still uses turn signals?). What's the programming behind that?!

Not enough long stretches of motorway with little traffic. In North America it's a different story.

....

It works well in much of continental Europe. In the UK, the traffic is too dense and drivers tend to drop in too close ahead for the radar on mine to be happy about the spacing.

I have exactly the same grumble. And I invite posters here to try to conceive of the edge case (if it exists) where you arrive at your destination in a (say) 30mph limit, but when you leave, there is no limit and hence the limiter is off.

The only one I can think of is where there is a time-dependent speed limit. But - in the UK certainly - that's only a motorway or dual carriageway. And you aren't stopping to park there.

I agree. I hardly ever have occasion to use the cruise control, but the speed limiter - esp in 30mph zones - is invaluable.

The only snag is that it won't apply the brakes going downhill (in order to overcome the acceleration effects caused by gravity). If it could do that, it'd be perfect.

For 30 zones, I set the limiter to 31 (checked it with a satnav).

41 for 40, 52 for 50.

Mine does retain the last limit set, but leaves it at "pause" rather than "on".

Sounds like fault rather than feature.

Works fine because it can see that the satellites aren't visible for a bit, like with tunnels.

Doesn't need to be little traffic, the best cruise controls allow you to specify the distance from the car in front of you to travel. So it is completely automatic when you come up to a car which is moving slower than you want to cruise at, so you decide when to overtake if you want to do that, or just cruise at the other car's speed.

The main thing none of them currently do is track the speed limit when you come to a town, slow down thru the town and speed up again once thru the town.

Some of Hondas will actually continue cruise thru traffic jams, stopping and starting the car completely automatically.

If had my way a speed up device should be fitted to cars to get the wankers up to the speed limit.

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