Sprinkler systems rely on a series of special wires that send an electric signal from the timer to the valves. This signal turns the valves on and off, controlling the flow of water to individual sprinkler zones. These wires are color coded for ease of use, and are generally waterproof. If a wire becomes frayed or damaged, it can short out the connection on that line. Repairing a shorted sprinkler line requires you to install a new wire in its place.
Things You'll Need
Set your timer to the "test" position to run each zone for 30 seconds. Watch the sprinklers to see which zone does not turn on properly. This is the zone requiring repair.
Set the sprinkler timer to the "off" position, and then unplug the timer from the alternating current outlet.
Open the sprinkler control timer to expose the series of colored wires connected inside. Each zone relies on a single white wire for the ground connection, and a single colored wire for each zone. The zone numbers are marked next to each colored wire.
Place a screwdriver into the screw that is holding the damaged wire for the zone number observed as broken. For example, unscrew the red wire from zone 1 if the first zone did not turn on properly.
Remove the wire from the damaged zone.
Open the sprinkler manifold box outside the house. Unscrew the cap from the same colored wire as the one removed from inside the timer control unit. Pull that wire out of the connection cap.
Run a new sprinkler wire, preferably with the same colored line, from the sprinkler timer to the manifold box. Follow the path of the previous wire bundle for easy access from end to end.
Place one end of the sprinkler wire into the empty slot on the timer, and turn the screw clockwise until tight to lock it in place.
Place the other end of the new wire into the connection cap from which the old wire was removed, and twist the connection back together.
Plug in your sprinkler timer back into the AC outlet and set the dial to the "test" position to check the new connection.
Always use electrical wire specifically marked for in-ground sprinkler use.
Never work on a timer plugged into an AC outlet.