I have a pool vac and the electrical cable to the vac has no continuity. I had this problem before and they cut a part of the cable and reconnect it to the unit. If I am to cut the cable the then hook it back to the unit. How will I know where the cable is kinda 'broken' at that side? Thanks. It is a Aquabot Turbo T. Unit ok as I had serviced it last year but the cable has a problem.