Volt meter is essential when trouble shooting an electric valve system. MRWETTECH gave you the correct process. Hopefully it's not a cut wire. If I were you, I would invest in a better timer if that's the problem ( and send the Orbit into orbit ). Rainbird, Toro or Hunter I would recommend (Not from Lowes or Home Depot!)
Richard Kersten
S&R Sprinkler Systems and Landscaping, Inc.
Destin, Florida