Electrical Questions? Ask an Electrician Online.
This is a sign of a loose connection or a broken wire inside imthe insulation.
First check the connectiion of the wire. Once you are sure it is good wiggle the wire without shoving it into the wall . If the light blinks on and off it is bad under the insulation
Using both hands to wiggle the wire you will be able to isolate
Where it is bad . If it is too short to connect after the problem has been cut out there are splicing connectors available in the electrical departnent of the big stores.
I will be glad to answer any questions you may have.