I'm swapping out a controller in the morning, that toasted the controller connections to zones 8 & 9. Fortunately the valve that was on zone 9, was in the same valve box as zones 10, 11, & 12. First I swapped wire(s) at the clock. After that didn't work, I was able to swap wire(s) in the valve box, and the clock. That told me that the zone 8 valve was ok, as was the multi-wire strand.
Mick
Irrigation Contractor
Certified Backflow Assembly Tester