Hey Mitchgo-
Last night I stopped by Menards and bought one Rain Bird solenoid, but it was so unpleasantly windy I didn't work on the issue.
Tonight when I got done mowing I turned on the water, plugged the controller back in (the display was completely blank) and reset the date and time. The programs I had set the night before were still in the memory (non-volatile memory like you said). And by the way, the 9V is rechargeable (I opened the front panel and it states to use only a rechargeable 9V battery on a sticker inside). So it looks to me like the battery is shot since it wouldn't run the clock for 48 hours.
Now, on to the good stuff. I ran the start-up test program and everything tested out fine, except zone 10 won't shut off unless I turn the water off. I get no fault codes on the controller and no clicking in the valve boxes.
and
When I was messing around in the valve box that valve 10 is in the other night, I did turn one of the solenoids a quarter turn and turned it back to see if that would stop the clicking. So I thought that maybe I didn't get it turned back off, but that is not the case as I have it turned as far clockwise as I can turn it by hand (and I think it was one of the other three valves and not number 10).
Funny how issues can change so dramatically.
I do have a VOM and will check the resistance in the various lines. Am I doing this on the controller's circuit board or at the wires in the valve boxes? I assume in the controller, otherwise it would not be checking the run of wire for continuity from the controller to the valve.
My system is on city water rather than well water, so it would really surprise me if there was something (like a pebble) causing the valve to hang open. I also assume that a failed solenoid can cause a valve to remain open, correct?
And Mr. Boots...if the controller was set to the "off" position, it shouldn't be actuating the solenoids even if it was plugged in while the water was off. That occurred to me during the work day today after I replied to you. I am still at a loss on the reason for the clicking.
Thanks for the info Mitchgo.