Bad solenoid
The word solenoid seems to be a catch phrase with the public. I'd be willing to bet that 500 people have told me they have a bad solenoid. They've been correct on 3 occasions unless the wires have been broke off somehow. Dogs love to chew on wires. Try this. Disconnect one of the wires from the solenoid itself at the valve. Now turn on the controller to see if you still have a short. If you do it's the wiring between the controller and the valve. If not then it's the solenoid. Also I'd be willing to bet you can find a replacement solenoid for any rainbird valve only 12 years old. Try Ewing or John Deere. It sounds like you said that you moved the wire to a new terminal on the controller and have the same problem. If you determine it's not the solenoid look for an unused wire you can use to replace the one that shorts out.
This post has been edited 1 times, last edit by "mrfixit" (Sep 11th 2008, 10:23pm)