The controller identified high voltage on the Pump/Master valve, or an open circuit. If you are unsure which fault you have (short, or open circuit), go to the "Events" tab of your controller page and make sure the "Description" column is visible. It will show you if the issue is a short or an open circuit.
What might happen as a result of the issue?
If you have a master valve or pump installed, all watering cycles will be skipped until the problem is fixed. If you do not have a pump or master valve installed, you need to disabled them in SmartLink.
The problem may be the result of a defective master valve solenoid, pump start relay, or field wiring. An open circuit issue can be a mis-configuration where the controller is configured to use a pump or master valve that is not actually required or installed.
What to do...Steps for a Solution
If you do not have a pump or master valve installed, then go to your controller in SmartLink, and hit the "Advanced" tab. Scroll down the page until you see the "Master Valve Enabled" section. Newer panels version 10.00+ may also have a "Master Valve 2 Enabled" section. De-select the check boxes for your zones, and hit save. After hitting save, select to "Send" the program at the top of the page. This should prevent future Master Valve "Open" faults.
If you do have a master valve or pump installed, be sure to separate and insulate all conductors carefully taking care not to damage wire insulation during installation. An electrical “short” (contact) between the valve wires and another source of power can damage the controller and create a fire hazard.