Unfasten the line that leads to the pump. Place the loose end in a container of water. Open a faucet. Start the pump. The water in the container should be drawn out by the pump and water should run from faucet. If not, you have a failing pump or the inlet and outlet lines are backwards.
There may no better way to configure the tanks and piping but what you have pictured looks like an accident waiting to happen. It looks like the tank outlet piping is very close to the ground. I would suggest you add a couple of elbows and try to get the lines further up. towards the frame.
