DDC-4 Controller Programming Guide & Troubleshooting

Complete Setup Procedure for Toro DDC-4

If your DDC-4 controller appears programmed correctly but valves don't activate—even in manual mode—follow this structured checklist.

1. Verify Wiring Before Programming

• All zone wires secured on their respective terminals.
• Common (white) wire connected to the C terminal.
• Rain sensor jumper installed on SEN terminals if no sensor is used.

2. Full Reset & Programming Sequence

1. Press RESET to clear memory.
2. Set Time/Date: Dial → SET TIME/DAY → enter Year, Month, Day, Time.
3. Set Run Times: Dial → RUN TIME → select Program A/B/C → enter minutes per station.
4. Enable/disable Master Valve after last station.
5. Set Water Days: Dial → WATER DAYS → choose Calendar, Interval, Odd, or Even.
6. Set Start Times: Dial → START TIMES → up to 3 per program.
7. Optional: Set % Scaling (Seasonal Adjust).
8. Test: Dial → MANUAL → assign run times → Dial → AUTO-RUN to start.

3. If Manual Run Counts Down but Valves Don't Open

• Confirm 24–26 VAC at controller terminals (common to zone wire) when station is active.
• If voltage is present, check valve solenoids and field wiring.
• If voltage is absent, the controller's output stage may be damaged.

Download the full manual at Toro's support site for diagrams and advanced features.