Symptoms
- One zone doesn't run at all during a cycle
- Other zones work fine on the same controller
- Manually activating that zone from the controller does nothing
Likely causes
- CommonFaulty solenoid on that zone's valveSolenoids are the electrical component that opens the valve and commonly fail individually.
- CommonBroken or corroded wire connection to that zoneWire nuts and splices buried underground can corrode over time.
- PossibleDebris stuck in the valve diaphragmDirt or debris can prevent the valve from opening even with power present.
- Less commonController station output failureA single zone's output on the controller board can fail while others work.
What to do
- Run the zone manually from the controller and listen at the valve box for a clicking sound from the solenoid.
- If no click, test the solenoid using a multimeter for continuity, or swap it temporarily with a working zone's solenoid to isolate the problem.
- Open the valve box and check all wire connections for corrosion, looseness, or breaks.
- If the solenoid clicks but water doesn't flow, open the valve manually (bleed screw) to check for debris in the diaphragm.
- Clean out any debris from the valve body and diaphragm before reassembling.
- If wiring is the issue, replace the connection using waterproof wire connectors rated for underground use.
Tools and parts
- Multimeter
- Screwdriver
- Waterproof wire connectors
Sprinkler valve solenoidSearch: “sprinkler valve solenoid replacement”
Waterproof wire connectorsSearch: “waterproof wire connectors irrigation”
When to call a pro
An irrigation technician can trace a wiring break underground using a wire locator if the fault isn't visible in the valve box.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.