I have a Toro Greenkeeper 212 about 20 years old. I have 4 zones in the A program (no other programs). This year when getting the system running, I noticed a problem in zone 4. There are 10 sprinklers in zone 4. The bottom 5 come on and run in every zone. The top 5 run correctly when the program gets to zone 4. It cuts off correctly.
What is wrong with the bottom 5 that run with every zone? Is it a programming issue in the controller, or is it a faulty valve for the bottom 5 sprinklers?