SPRINKLER TALK FORUM - You Got Questions, We've Got Answers

if you have a seperate valve manifold to feed zones 5-9 in the back chances are the wires been cut or a bad common connection.you should call your service co. to properly troubleshoot the system.

Could be a problem with your common wire like water miser said, or it could be that all of the backyard zone wires were cut. It is unlikely the problem rests in the controller if the front zones work, or in the valve or valve solenoids, because I doubt it if they would all crap out at once. Have you done any digging or construction recently? I would suggest a qualified contractor come out and run a few electrical tests on your system to see if the problem lies within the wiring.