New member here. I’m trying to diagnose a glow plug circuit issue. My glow plug light only comes on for 1 second before it goes out regardless of what the coolant temperature is. I have the service manual for the tractor but it’s not very helpful. It says it should have a go relay, gp timer and gp controller. All I’ve found are 2 relays …one they call a preheater relay and the other is the gp relay. I cant locate a timer or controller. I do have an engine control module so is that now where the timer and controller function is located in? Any help would be appreciated.