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The chip in my UK passport failed to work when I recently re-entered the UK. I have two queries about this.
1) Is there any convenient way of checking whether the chip is actually functioning correctly?
2) I wish to travel to the US soon. If the chip is not working, is it essential to get a new passport in order to be admitted to the US? Apart from the matter of the chip, my passport is not damaged visibly in any way.