Why won't our Citroen's sat nav work with a 7-digit postcode?

Can you tell me what is the point of a built-in car satnav (in a 2-year-old Citroen) that won’t let you input the last two characters of a postcode, so it only takes you to a town, not to the exact address as required? You could do that with a glance at a map. When in the Cotswolds recently, we had to use OS map as the satnav map just showed a blank area surrounded by A- and B-roads.

Asked on 3 August 2013 by ET, Winchester

Answered by Honest John
Some systems are designed for European 4-digit postcodes. Others are designed for the much more accurate 7-digit postcodes used in the UK and in Japan, but in very few other countries. An imprecise system can't be upgraded to become more precise but, owing to the influence of TomTom, most car manufacturer satnav now locates to 7-digit codes.
Tags: sat nav
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