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

So I have a 6 year old RainBird sprinkler system on a house we just moved into 3 months ago. I was out yesterday adjusting the heads to make sure I had the proper coverage becuase a have a couple dead spots and noticed that one of the pop up and spin sprinklers would pop up but not rotate. (Its a Rainbird 5000 type in my front yard in Zone 1) I also noticed that there were 2 popup and spray sprinklers that would pop up but no water would come out (in 2 different zones). I tried adjusting them but could not get any water out of them. (They are Rainbird as well).
I decided to go to Lowes and pickup replacement heads and swap them out with the bad ones. Simple enough right!? I unscrewed the Popup rotary (RB 5000) and installed the repalcement. I got the EXACT same model so it was a simple swap. Before moving to the next 2 sprinklers I went to the control and turned on Zone 1 to fine tune the coverage of the new head and now the sprinklers wont come on. I can tell a litte water is making it through because it trickles out of all of the Zone 1 heads but there is not enough pressure to pop them up. I even tried to advance through the rest of the zones and nothing happens on ANY of the zones now. I went ahead and replaced the other 2 heads (easy.. unscrew old and screw in new). When I finished that I tried to run the system again and STILL nothing happens.
I opened the valve control box and manually started each zone one by one and I get the same result. Nothing happens.
I have verified that the main valve is OPEN and that the water is on. I reset the control panel as well. System is fed of off city water and worked just fine the morning I changed out the 3 heads.
Any idea what to check next? How would chaning 3 broken heads cause this?!?!

Quoted from "hi.todd"

I did not even read the whole post. You probably cut the common wire that ran in the same trench as one of your sprinkler heads is in.

Either that or the rain sensor is activated an it is a coincidence.

Not sure how I could have cut a wire when I didn't dig anything. Just unscrewed the heads and replaced them.

Rain sensor is in bypass as I thought about that too.

Quoted from "mrfixit"

Did you turn the water off somehow? I've seen it done more than once.
People shut off the water to the sprinkler system and forget they've done it.
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Maybe you cut a wire going to the master valve?

I triple checked the water is on.

How can I determine if the master valve wire is cut? If the common wire was cut wouldn't each zone still start when I manually start them at the control valve box in the ground?

Quoted from "mrfixit"

How do you know the water is on to the sprinkler system if none of the valves come on manually?

Water comes out of zone 1 but it's very low. Low enough that the heads won't pop up.

Quoted from "mrfixit"

Do all the valves do this?
A broken pressure regulator could cause low pressure to all the valves.
A shut off valve that's partially open. Sometimes a gardener will fiddle with it.
A bad master valve.
Is there a pump? Is there some sort of filter on the line?
Have you turned the water off at the meter recently? Sometimes a plumber will not turn it back on all the way causing low flow.

Thanks for your help.

To answer your questions.
1. Yes. None of the zones work but there is a very little water passing through each of them.
2. Where would I check for the broken pressure regulator?
3. Where would I check or a broken master valve?
4. There is no pump.
5. Nope. I was down there tonight and turned it off and all the way back on to be sure.

System ran just fine yesterday morning. All I did was unscrewed the broken heads and installed new. How could that cause this?