First, to make sure that poor contact is not causing the issue, since you are positive that the batteries start out good. Remove them from the camera and clean the metal battery contacts inside of the battery compartment and on the battery with a q-tip and alcohol. The connection is very critical and a very small amount of residue or dust can inhibit the power transfer. Also, check how well the battery door shuts and if necessary adjust the metal contacts by gently prying them with a small screw driver to increase the tension. It is a known issue that as digital cameras that use AA size batteries age, they tend to require a little more power due to deteriorating parts and surface residue. Lens movement uses the most power. That is why the connection is so critical. Finally, for this step, because even I have made this mistake, while rushing, please, double check the orientation of the batteries. (see the attached photo).
If unsuccessful, try powering the camera on with the memory card removed.
Please let me know the result.
Please keep in mind that my diagnosis & solutions provided are directly dependent on the accuracy of your description of the problem. As with any "do it yourself" fixes, success is a "team effort", since I can't see or touch the camera, and relies on the customer's manual dexterity and ability to follow the instructions well. If the "do it yourself" approach doesn't work out for you and you need conventional repair, please let me know.
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