Why don't manufacturers fit speed limit warnings as part of satnav systems?

I recently received a Notice of Intended Prosecution from Norfolk Constabulary for exceeding a 30mph speed limit in Norwich by 5mph. I will be allowed to attend a Speed Awareness Course, which I look forward to. I have no beef with being caught for exceeding the speed limit. Nor do I have any issue with existing speed limits, which are there for excellent reasons. If I have a beef, it is with car designers. Modern satnavs are able to warn us aurally when we exceed a pre-set speed limit. If we are so concerned about safety, why don't modern cars have such a system fitted?

Asked on 9 February 2013 by JN, Midhurst

Answered by Honest John
Some GPS satnavs warn when you are in a limit, but only if the location of the limit was pre-programmed into the software, which could be a couple of years out of date. This is why ‘Intelligent Speed Adaptation’ that controls the speed of cars by GPS was a non-starter. New camera system driver aids in Fords, Volvos and GM cars actually spot speed limit signs and warn drivers accordingly. Like you, I don’t understand the public obsession with analogue speedometers. Give me digital any day.
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