Locating Valve

Got a situation. I have tried tracking a valve and having no luck. There’s electrical lines running from the unit (green box) right to the hook up on the wall beside my irrigation controller. Having too much interference and just can’t get a solid track. Have also tried Chat-R-Box and still no luck. Maybe solenoid is no good. Any other suggestions to find this valve other than starting at a head digging and praying? Thanks