I would recommend replacing the entire cable, if one part has been damaged by rodents then it seems probable that other areas of damage exist and are likely to cause future problems.

This isn't as straightforward as the cable is buried in walls/ceiling. It's only one section as the ring has been broken and it's functioning as a radial on one leg of the ring. The damaged section is difficult to trace even using the standard approach of splitting the ring taking each socket off and testing.

That must mean that you have identified which section of the ring is damaged.

I agree with Broadgage that it would best to replace the whole section. If you are going to have to dig out at least a couple of feet, making it six feet won't look much worse, and the decoration will still have to be made good.

There is also the question of joining the cable, which is avoided if the whole section is replaced.

You may be able to get an idea where the short is by measuring the resistance of the two portions of the damaged section - its distance along the section will be proportional to the resistance. Granted your low resistance ohmmeter may not make much of a distinction, but it should give an idea.

That must mean that you have identified which section of the ring is damaged.

I agree with Broadgage that it would best to replace the whole section. If you are going to have to dig out at least a couple of feet, making it six feet won't look much worse, and the decoration will still have to be made good.

There is also the question of joining the cable, which is avoided if the whole section is replaced.

You may be able to get an idea where the short is by measuring the resistance of the two portions of the damaged section - its distance along the section will be proportional to the resistance. Granted your low resistance ohmmeter may not make much of a distinction, but it should give an idea.

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