Why are you using those type of heads? Use the Rainbird 5004 or 5012. These heads will retract into ground and you won't have to worry about the lawnmower hitting them. Install these so that the top of the head is flush with the dirt level, not turf level but dirt level.
I agree with Mitchgo. Also, there should be a flow control on the valve. See if you can turn the flow control off and that should at least help slow down the water flow.
Ask your distributor to check other locations in mid-west and south east.
Unplug controller. Unlock and remove all modules. Wait a minute or so. Re-install modules and lock into place. Plug in controller. If you still have same problem, then you need to replace just the MOD 1.
The problem could be that the port for zone 3 is not producing power for the valve. Try taking the wire out of zone 3 port and put in, say zone 2, and turn on zone 2. If valve works then it is the controller. If it does not work then you most likely have a broken wire somewhere on zone 3 wire.