I apologize in advance for my rookie status but I have a problem I cannot solve. Here are the facts: Irritrol-Total Control TC-12 13 year old system 9 valves wired Misc valves (Hit, Buckner, etc.) Master Valve Client calls with screwed up system. I arrive and start at the controller. You fire a zone and the controller is sending 24vac to all zones at once. OK, swap out the module, everything is cool, the controller only sends the 24vac to the zone selected and the MV. One less problem as we've proved the electrical part. The problem is, the entire system is trying to operate at one time (even without 24vac going to other valves. I ohm'd out a solenoid at 21 so that is within spec's. I pulled a couple of bonnets and found some crap on the diaphragm but nothing major. Another test I performed was pulling a wire on a valve not selected (but is trying to run) and it continued to push water out of the heads. What am I missing? It's gotta be something obvious that I've just convoluted.