Thanks for all the advice so far. Sorry for not responding, the system randomly started working after I posted last time I posted. It seems to be sporadically not wanting to work (case in point, it's not working again).
@hi.todd - The rain sensor is set to "off" on the control box. It had rained when I posted it, but it hasn't rained this time.
@mrfixit - Yes, I am certain the outlet is working. Anything I plug into it works perfectly.
@Double_kyan - This is where my complete and utter incompetence comes in. Are the sprinkler valves on each sprinkler? Or are they somewhere else?
Again, thanks for helping out someone who has absolutely no idea what he's doing.