Even wired correctly it could still shock (8)
I believe the answer is:
telegram
'shock' is the definition.
Although both the answer and definition are singular nouns, I cannot see how they can define each other.
I cannot understand how the remainder of the clue works.
Can you help me to learn more?
(Other definitions for telegram that I've seen before include "Message transmitted by wire" , "Message once sent by radio or electrical signals" , "Now obsolete communication over a wire" , "It may bring word" , "Electric message" .)