You need an ohm meter to see if there is an open leg or a short down hole. Also need to check for correct voltage getting to the motor. You may have a bad pressure switch that will just not let the power through. I hate to tell you this but, 7 years is the average life of a submersible. The fact that you already got 10 years is probably because you have two tanks. The more tanks, the less cycling on and off, and the longer the pump will last.
If it is the pump fried, you should consider a Cycle Stop Valve. They will make the pump last longer than if you had a whole room full of tanks.