I am troubleshooting an old system where none of the valves are coming on. The owner is having to manually turn them on to water his lawn. I checked the controller and there are 24 volts coming out of it. I cannot get an ohm reading at the controller when testing the resistance. My conclusion is that there is a break in common wire between the controller and valve 1. But I also get a 24 volt reading at the wires going into valve 1. My question is: could I still be getting a voltage reading at valve 1 even though the common wire could be broken somewhere in the ground? Could the common wire be grounded at the break in the ground?