When you said that you manually turned on the valves did you mean using the electronic on/off at the rainbird controller or the manual on/off at the valve ?
When you tested the solenoid resistance, did you do that near the sprinkler valves or at the controller end ?
Without knowing more about the layout of your system (location of controller and sprinkler valves and cable connections between them) it is difficult to guess but I would start looking at the common wire from valves 1-4 to the 1st ESP module.--
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