When one sprinkler zone stops working
A single dead zone has a short list of causes, most of them inexpensive. How to narrow it before the call-out.
One zone failing while the others run normally is a helpful fault, because it rules out most of the expensive possibilities immediately. If the pump, the mains supply and the backflow preventer were the problem, nothing would work.
The usual causes, cheapest first
- The controller is not sending the signal to that zone. Test by running the zone manually at the controller.
- A failed solenoid on the zone valve. Valve replacement is published at $70 to $300.
- Damaged wiring between the controller and the valve, published at $60 to $100. Common where landscaping or digging has happened.
- A stuck or debris-fouled valve, which sometimes clears with cleaning rather than replacement.
- A broken lateral pipe on that zone, published at $150 to $400. Usually shows as a wet patch or as heads elsewhere on the zone running weakly.
Source: HomeGuide, Sprinkler System Repair Cost, 2026
Narrowing it yourself in ten minutes
- Run each zone manually from the controller and note exactly which ones work.
- If the zone does not start at all, listen at the valve box for a click when it is switched on. A click suggests the solenoid is receiving signal.
- Walk the zone with it running and look for wet patches, sunken ground or unusually green strips, all of which indicate a leak.
- Note whether heads on the zone are weak rather than dead, which points at a leak or a partial blockage rather than a valve.
Batch the work
Labour dominates small sprinkler repairs: a head costs $3 to $30 as a part and $50 to $120 fitted. Walking the whole system with the zones running, listing every fault, and giving the contractor the complete list turns three visits into one.
It is the single highest-return ten minutes available on a sprinkler system.