Speed limit warning

ToddG · Post by **ToddG** » Mon May 06, 2024 2:47 pm

Does anyone know if the speed limit warning displayed on the dashboard display is based on camera recognition of street signs, or map data. It is not clear in the manual.

buzyg · Post by **buzyg** » Mon May 06, 2024 4:43 pm

Most are based on map data.

Argyll Andy · Post by **Argyll Andy** » Mon May 06, 2024 5:48 pm

I think it must be some sort of combination as mine picks up temp signs like mobile works for grass cutting etc and sometimes stays on the restrictions until it sees a “proper sign” like another speed limit or a national speed limit roundel as the temp ones don’t have any notification that you’re through the restriction.

ToddG · Post by **ToddG** » Tue May 07, 2024 12:47 pm

I use Waze (Android Auto) and know the speed limit is map based. But Waze maps are updated regularly, while the cars maps are not. Seeing as the car has a camera for lane keeping, I thought perhaps it 'reads' the speed limit signs. But I think it is map based.

Argyll Andy · Post by **Argyll Andy** » Tue May 07, 2024 12:59 pm

ToddG wrote: ↑Tue May 07, 2024 12:47 pm I use Waze (Android Auto) and know the speed limit is map based. But Waze maps are updated regularly, while the cars maps are not. Seeing as the car has a camera for lane keeping, I thought perhaps it 'reads' the speed limit signs. But I think it is map based.

If it was only maps based it wouldn’t do as above and pick up temp signs

ToddG · Post by **ToddG** » Tue May 07, 2024 1:47 pm

Argyll Andy wrote: ↑Tue May 07, 2024 12:59 pm
ToddG wrote: ↑Tue May 07, 2024 12:47 pm I use Waze (Android Auto) and know the speed limit is map based. But Waze maps are updated regularly, while the cars maps are not. Seeing as the car has a camera for lane keeping, I thought perhaps it 'reads' the speed limit signs. But I think it is map based.
If it was only maps based it wouldn’t do as above and pick up temp signs

It would be great if that is correct. I have got so used to looking at the Waze speed limit, I don't even see speed limit signs anymore...

BTW, the camera based detection may be one of the driver assist options. I have 5AS (single camera), but 5AU (triple camera) is a higher spec.

Argyll Andy · Post by **Argyll Andy** » Tue May 07, 2024 2:20 pm

ToddG wrote: ↑Tue May 07, 2024 1:47 pm
Argyll Andy wrote: ↑Tue May 07, 2024 12:59 pm
ToddG wrote: ↑Tue May 07, 2024 12:47 pm I use Waze (Android Auto) and know the speed limit is map based. But Waze maps are updated regularly, while the cars maps are not. Seeing as the car has a camera for lane keeping, I thought perhaps it 'reads' the speed limit signs. But I think it is map based.
If it was only maps based it wouldn’t do as above and pick up temp signs
It would be great if that is correct. I have got so used to looking at the Waze speed limit, I don't even see speed limit signs anymore...

BTW, the camera based detection may be one of the driver assist options. I have 5AS (single camera), but 5AU (triple camera) is a higher spec.

Having had a think about it there’s definitely something reading “live” data.

The same thing happened to me twice, both times on a forum run, I always activate cruise when approaching a village/town etc, particularly when we were in Wales. Both times it was one of those speed limit signs that is a digital type display made up of DOTS forming the numbers. It wasn’t one of those green smiley faces if under and red scowling one if over. It was an actual speed notification sign. When a change of limit is approaching the HUD flashes SET for the new/reduced limit and I just press it

Both times I’d entered a 30 mph zone with one of those signs, both times the car dropped multiple gears and took for the hills, in sports+ mode too so progress was rapid. Looked at the heads up display and the cruise was set at 80 mph. It has misread the DOT sign both times, I’d hit SET without checking and the cruise control was now set to 80 in a 30

My car had all option packs including active cruise control so don’t know if functionality differs with different options/packs

The sign was sort of like this but the numbers were in red, s**t myself both times it happened

if it relied solely on maps or already populated data on both these occasions when I pressed SET it would’ve done so at 30

sars · Post by **sars** » Tue May 07, 2024 4:58 pm

It's part of the driving assistant pack, automatic speed limit recognition, good option but it can get a little confused sometimes.

ori · Post by **ori** » Tue May 07, 2024 7:32 pm

sars wrote: ↑Tue May 07, 2024 4:58 pm It's part of the driving assistant pack, automatic speed limit recognition, good option but it can get a little confused sometimes.

Correct!

PSQ777 · Post by **PSQ777** » Tue May 07, 2024 8:42 pm

It must be doing something live because I've seen it react to motorway matrix sign speed limit changes pretty quickly.

dr_john · Post by **dr_john** » Wed May 08, 2024 7:12 am

My previous g29 had a windscreen replacement which blew the fuse in the forward facing camera, rendering it out of action. It took a few days to sort it out, during which time the speed limit function was out of action.

Make what you will of that, but it seems obvious to me that the camera is at least an important part of this feature.

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