Question
I am at wits end with the irrigation system.  It is an outdoor Rain Dial Model RD-600 (not sure).  The manual I have is for RD-600, RD-900 and RD-1200. The timer flashes when the set time to start water to pump into the line. A section of the water line is above ground. When you step on it or put your hands on it you can feel the brief surge of water entering the hose and then it stops and timer starts flashing. I would set a new time to start.  I would wait a minute and the same thing happens with the water running for about few seconds then stops and timer starts flashing.  The other day I did this 3 times and on the fourth try it started and ran for the 1 hour cycle that I had programmed. Today the water starts flowing with a 3 second surge and stops with the timer starts flashing.  I was told that the complet system in the ground; value/pump etc needs to be replaced and that the timer/clock is ok.  What is the problem?

Answer
Off hand I would say your controller is the problem. The other possibility is if you are using a pump, the pump circuit is drawing too much power causing the an over current fault.
You need to check the voltage output of the controller. Turn the controller to zone one and place one probe on the "COM" terminal and the other probe on the zone one terminal. You should see 23-27 volts, if not. Disconnect the #1 wire and retest. If this help the field wiring has a short. Next, disconnect the wire to the MV/PUMP terminal, turn on the controller. Test the COM and #1 terminal again. If the controller works without the MV/PUMP wire hooked then you should change the pump start relay. If the controller is still doesn't give you power this way, I would look to change the controller.
Hope this helps.

Matt