Quick answer: Multiple sprinkler zones running together can be caused by valves that are not closing, wiring faults, incorrect field-wire connections, controller configuration, or hydraulic problems that allow water through more than one valve.
Start with the controller
Run zones manually one at a time and note whether the controller indicates only the selected station. If the display calls for one zone but another also waters, the problem may be downstream from the programming.
Valve problems can overlap
A valve that does not seal completely can continue passing water while the next scheduled zone starts, making two areas appear to run simultaneously.
Wiring mistakes can energize more than one circuit
Damaged splices, crossed conductors or previous repair work can create unusual multi-zone behavior that requires electrical testing.
What information helps diagnosis
Note which zones overlap, whether the same combination repeats, and whether the unwanted zone stops when irrigation water is shut off.
See why a sprinkler system may not shut off and our sprinkler troubleshooting service.
