I had a valve that didn't work, the resistance measured around 39K at the controller. I am wondering what the cause of this high resistance. Is it due to insulation breaking down on a sharp edge somewhere and it shorts to wet ground? The locator was not very useful in locating this valve but with some logic and a lot of luck I found the valve. I ran another line out to the valve box and verified which line was the problem. I simply put in a new line. I have had no luck trying to find the location along the wire where the problem is located with a locator? Has any one else been able to find exact point of the problem?