Try this:
Disconnect the power to the sprinkler timer either by unplugging it or by turning off the breaker that supplies power to the timer, whichever is easier.
Disconnect the 9v batter if there is one.
Go have a soda pop.
when done with soda, come back and hook up the electrical power to the timer, then hook up the battery, IN THAT ORDER.
This will work 9 times out of 10. When we perform a service call for this sort of thing we call it "demagnetizing", but I'm not really sure if that is accurate.
Good Luck!
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Sprinkler Solutions, Inc.
Arizona and Colorado
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