Check that power is on. Receiver settings may have been changed. Cables or connectors may ave been damaged. Should be 15 - 24 volts DC and 150 milliamps current. Take care not to short the leads in the cable together Measure on ohm meter on LNB output socket Should show continuity.
Open circuit indicates a problem.
Water entry could cause damage. If all of the above methods have not succeeded in locating the fault, please contact the Help Desk for your area.