No power to the display panel. We recently replaced the 2nd pump and the heating element on our

Question

We recently replaced the 2nd pump and the heating element on our older model of a jacuzzi hot tub. We have electricity to the circuit panel but the tub display panel is not working to turn the tub on. Is there a easy way to test the circuit panel to see if it has gone bad or if it is somewhere between the panel and the display controls? Thank you