touching the contacts three times sets it in program mode,touch both contacts,it sounds like it is working,after changing the battery it should be ready to dive,just your date and time will be off. Take it for a dive or try it in a pool to see if it is working or not. It is a very simple to use computer,no fancy features,just your basic functions you need to dive air. It has been about 3 years since I have used it,I bought a new nitrox capable computer and sold that one on ebay. The only trouble mine gave me was when floating on my back surface swimming,somehow the water would hit the contacts enough times to put it in program mode,I guess I was lifting it out of the water,but you would have to go through the screens to reset to dive mode,it would not do program and dive at the same time,no dive info while in program.It would probably work better in a console mount rather than the wrist mount like I had it,but I prefer wrist mounting,it makes it easier to check your info,just looking at your wrist rather than messing around with a console.