Thank you for the replies. Yes, I understand the challenges when going up into an attic area, not fun at all:(
1) I suggest using a non-contact type of AC voltage detector. You will need access to the attic area where the cables are routed. Have an assistant help you by turning the light switch ON & OFF. While the circuit is being turned ON & OFF, take the non-contact voltage detector and scan each Romex cable in the attic. You should then be able to determine and confirm which Romex cable controls the lighting by using the non-contact tester. Once confirmed, turn the branch circuit breaker to the OFF position. Use a 2 wire lead AC voltage tester at the light switch to confirm that no hot conductor is present.
2) Once all is confirmed, you can then cut the Romex cable. Make sure the breaker is in the OFF position before you cut:)
You may or may not be able to remove the Romex cable out from the cinder block wall cavity, all depends upon how it was originally installed and available access to the cable. Once the cable is cut, you will need to install an accessible junction box with a blank cover plate in the attic area for the splices and then re-route the new piece of Romex cable to the desired area.
If you have any additional questions, just let me know and I’ll be glad to answer them for you.
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