04 fiesta spedo fault :/

[hulkfocus]

hey guys

my partner has an 2004 WP fiesta Lx and is having problems with the speedo....Every now and then the speedo will just die and then come back after a couple of gear changes or just by its self

also was going up the expressway and the speedo died and the whole car shut off

what would be the problem? Computer??

any help would be much appreciated!

thanks