on the blink

Presumably from an appliance with poor electrical connection blinking from intermittent connection.

• Audio (General Australian):

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on the blink

1. (UK, Australia, informal) Usually of a mechanical or electrical device, functioning erratically, malfunctioning; not working or not working well.

   My toaster is on the blink, making either charcoal or cold bread.

   • 1968, “I'm So Tired”, in John Lennon (lyrics), The Beatles, performed by the Beatles:

     I'm so tired, I haven't slept a wink / I'm so tired, my mind is on the blink

• (malfunctioning): on the fritz

• “on the blink” in Longman Dictionary of Contemporary English, Longman.
• “on the blink”, in Cambridge English Dictionary, Cambridge, Cambridgeshire: Cambridge University Press, 1999–present.