HI Neil
Checked "Garmin Device! ...........PartNumber>006-B1132-00</PartNumber><SoftwareVersion>390</
SoftwareVersion><Description>nüvi 1690</Description>

So I used Garmin Cure to install Original GCD from your earlier link (nuvi16xxEU_regionfileonly__390.gcd)

Everything installed Ok , But the shutdown still occurs when I press "System"

Tried pressing all other icons and it's OK ,just the System icon which has the problem