Speed readings

[asti1488]

Hi quick question
Driving along a road the speed shows 30 mph on the satnav but speed on dash shows 20 and bonging over speed sound if I go over 20. Why different speeds showing ?

 

[5teep]

That's a wild difference. I expect a car to show 1 or 2 miles faster than it's actually going (to save them being sued by all the speeders) but 10 miles??

 

[asti1488]

Unless the satnav and the road sign recognition are different versions and one needs an upgrade . Car is only a month old

 

[Alb]

Just switch off the speed sign recognition as it's easily misled or simply wrong.

 

[asti1488]

I’ll give that a try , cheers

 

[stevedee]

It seems to me that the satnav uses published data for speed limits (sometimes out of date) while the other speed is calculated from what the camera sees (sometimes wrong when it catches a glimpse of side-road speed signs).

 

[Ian Key]

They've reduced the speed limit from 40 to 30 on a road near me and the sat-nav still thinks it's 40 and with it being in a built up area with lampposts there are no 30 speed limit signs for the car's camera to see.

 

[Lovemyev]

They've reduced the speed limit from 40 to 30 on a road near me and the sat-nav still thinks it's 40 and with it being in a built up area with lampposts there are no 30 speed limit signs for the car's camera to see.

Same here.
One of the 20Mph roads close by, has been reverted to 30 Mph just recently.
It has confused the hell out of the car .
The cars camera will see the sign fine and advise of the 30 Mph but the Sat Nav detection is still convinced its a 20Mph.
Two systems fighting with themselves and not able to apply joined up thinking unfortunately.
There is definitely a “lag” between what is detects by the camera and the Say Nav and the ability to process the information quickly enough.

 

[Fred69]

It seems to use a combination of cameras and the GPS - as mine changed recently to mostly displaying "---" when the limit was 60, but then generally getting the lower speed limits right.

I randomly clicked into the navigation tile (which I don't usually use) and it was asking me to confirm data privacy settings. Once I accepted those, then the speed recognition returned to showing 60 more consistently.

No idea why it uses a combination - most frustrating not to have some kind of override when the cameras pick up a side road at 30 in a 50 zone..

 

[Micropop]

Yesterday I drove through an urban area close to a school. Speed limit is 30kph with speed bumps. Both satnav and sign recognition stated 110kph! . Maybe it had been adding up the last couple of speed signs!