Toro Zone 3 Failure: Controller Voltage Test After Valve and Pump Replacement

Zone 3 Works on Battery but Not from Controller

After replacing the pump and solenoid, zone 3 operates when powered by a 27 V battery pack but not from the Toro controller. This points to insufficient controller output voltage.

Controller Output Test

1. In the controller cabinet, remove the zone 3 and common wires from the terminal strip.
2. Activate zone 3.
3. Measure voltage between the zone 3 terminal and common. Should read 22–26 VAC.
4. Low or no voltage = controller fault. Good voltage = wiring or connection issue between controller and valve.