So I've got a new Ford does this, and it can operate in one of three modes selectable by the driver: 1. An advisory mode, where it dings at you if you bust the

So I've got a new Ford does this, and it can operate in one of three modes selectable by the driver: 1. An advisory mode, where it dings at you if you bust the speed limit. 2. Speed limiting mode, where it won't accelerate past the limit unless you override the limiter by flooring the accelerator. 3. Adaptive cruise control, where the cruise control will speed up and slow down to suit what it thinks the speed limit is The system uses a combination of speed sign recognition and and its satnav database. The speed sign recognition could be best described as "ok". What it really struggles with is construction and other temporary speed limits such as school zones, particularly on side roads. There is a spot near me on a 100km/h arterial road where if I'm using adaptive cruise, the car will detect the 40km/h construction limit on a side road and then brake hard to slow from 100 to 40 for no proper reason. This is very dangerous, tantamount to brake checking, which is a traffic offence that I otherwise could properly be fined for.