Disconnect cables at aux + and - terminals. If system resets without fuse blowing then there must be a short circuit between one of the cores. If you have a test meter check for continuity between each pair of cores in each cable. There should be no continuity if there is then that is the faulty cable/ sensor or whatever is on that zone. If no meter reconnect each cable in turn until fuse blows, faulty cable found. Much easier with a meter though!
alan mckenzie, July 2019
