Make sure battery is good: if in doubt install a new cell.
Make sure battery connector is good and is firmly attached to circuit board.
Is the top lid making level (flush) contact with casting?
See if you can reach in on the back right-hand side of the unit (with lid up) and push down on the small black actuator button located on the casting part of the unit.-If unit exposes by pushing on button, the top lid (cover) is out of adjustment. This can be fixed by reaching in with a small flat head screw driver and carefully prying down on the actuator tab located on the bottom side of the top cover. -Otherwise, please idicate problem and send in for Flat Rate repair
