Question
My sprinkler system will run the first two zones and then shuts off.  If i run a test, all of them work except zone three.  They all worked fine at the end of last summer.

Answer
Hey John, I would suspect that the solenoid on valve #3 is bad and needs to be replaced. Try this first and see if this corrects the problem. The solenoid simply un-screws from the top of the valve, and you need to hook the two wires back up to the two wires you un-hook from the old solenoid. Good luck and have a great day.