To fix you would need find tamper fault, set a multimeter to resistance and place on 2 green wires places in tamp, you should see a reading near 0, if not you will need to break down and test each zone wire individual until fault is found, in contact the tamper is magnetic, on pir the tamper is mechanical switch or electronic contact.
The junction box is where each tamper is wired in series so that if loop is broken tamper loop the alarm goes off.