Toro Controller Won't Start System After Power Fluctuation

System Worked, Then Power Flutter—Now Won't Start Automatically or Manually at Controller

System ran fine twice this spring. Today: no start via timer or controller manual. Valves work manually at valve. Fuses look OK. Power flutter night before.

Diagnostic Steps with Multimeter

1. Rain sensor? Check sensor terminals—should read open (infinite ohms) if dry.
2. Solenoid resistance – Controller off. Meter on ohms: black on common, red on each zone terminal. Expect 20–60 ohms.
3. Controller voltage output – Meter on VAC: black on common, red on each zone terminal during manual start. Should read ~24VAC.

Interpretation

• Good ohms, no volts → controller output stage fried (power surge).
• Bad ohms → wiring/solenoid issue.

Power surge likely damaged controller. Replace if no voltage output.