I dont have any sketch yet. Im not exactly sure how to incorporate the motion sensor. I have now read that if i remove power to the display each time it turns back on it will have to initialize. I dont want to do that. Its a display on the wall when I walk up to it I want it to come on and display the pool temp. I was trying to extend the life of the display by turning off the backlight and the characters on the display.
Here is a link to the display
LCD Info
Here is info on the motion sensor.
Motion sensor info
I was thinking I could power the LCD from the arduino