Had to take mine apart to remember what was inside. Two screws in back, circuit board under the rubber keyboard protector, 12 vdc battery with negative to left side (diode d1 side), spring should be on that side, positive connector to right side. Battery is #L1028/EL12/VR22 type alkaline cell. If your spring doesn't slip over the negative terminal, then it should be held in place by a rivet when made...like mine. My circuit board is labeled pcb490 rev0 and on next line is ausp1 au-1. Don't know if there is a lipsheet on
www.lci1.com to tell you how to reset system if need be. My remote lives in a tray with its battery removed. John