I've got a residential that has an old Lawn Genie controller. The real estate company I work with called and wants to get the sprinkler system running so they can lease the house. The controller is fried so much it is even missing the plug cord. I buy a RainBird controller to replace it but notice that all the wires coming out of the wall are plugged into a zone 1-7. Typically white is used for common but it has been plugged into zone 3. I tried to locate a valve box to see what color was hooked up to each selenoid but all the valve boxes are covered. Any suggestions on how to determine which one is common without locating the valves and can the valves be located with a locater without a usable controller wired right or knowing which wire is common? Any help would be appreciated.