4 of the 6 zone won't work

[MP]

My sprinker unit is 13 yrs old, which has a 6 zone sprinker system. Zone 1,2,3,4 won't work. Zone 5 and 6 works fine.

Issue:
The first 4zones won't come on. The wiring all look OK. When I run the unit on manual mode and turn on the 1st. zone, I noticed that there is voltage (approx 10-15 v) on zone 2,3,4. However, zone 5 and 6 have "0" volts. So there is bleeding of voltage on zone 1,2,3,4 which ever zone I make it active.

When I go to manual mode and set zone 5, the voltage on this zone is 20 V and all the other zone show zero voltage. Ditto for zone 6 also. Which I guess should be the way it should work.

What is going on on zone 1,2,3,4. What should I do to fix this issue. I thought the control box is fried and just replaced a brand new Rain Bird system. Please help .... ....appreciate your help in advance.

MP

[jimbo]

First, I would not rely on any voltage meaurements taken with all the wiring connected. I would disconnect all wires at the controller, and repeat your test measurements. My first suspect would be an open neutral ( probably white) wire involving one or more of those 4 valves. Such an open can cause you to get confusing voltage measurements like you did. You will just need to disconnect things and make some contiuity measurements on all the wires.

[the wet maker]

are you sure all your solenoids are good?