1972 according to this web page: http://www.lmn.lib.al.us:90/record=b1245989
The Impossible Dream - Andy Williams album - was created in 1966.
Impossible Dream
Honda Impossible Dream Sung by Andy Williams Honda 'Impossible Dream' was launched on December 2, 2005, a panoramic 2 minute television commercial featuring British actor Simon Day riding and driving on the roads and waterways of New Zealand.
The Andy Williams Show - 1962 - 1.9 was released on: USA: 22 November 1962
The Andy Williams Show - 1962 The Andy Williams Magic Lantern Show Company was released on: USA: 4 May 1969
The Andy Williams Show - 1959 was released on: USA: 7 July 1959
The Andy Williams Show - 1962 was released on: USA: 20 September 1962
The Andy Williams Show - 1969 was released on: USA: 20 September 1969
Biography - 1987 Andy Williams was released on: USA: 23 November 2003
ANDY WILLIAM'S - "THE IMPOSSIBLE DREAM" Moron
Andy Williams sang the song, originally penned in 1965 for the musical 'Man of La Mancha', in the Honda advert.It appears on the album "The Very Best of Andy Williams".I haven't been able to tie down a date for Andy's cover of this song.- - - - -Now I read your question again, I think you want to know when it was used. It was in 2005.
The Andy Williams Show - 1962 - 1.1 was released on: USA: 27 September 1962