My camera had slipped & fallen down & I had got it fixed at Canon Service centre in India. After repair I observed that after a few photographs the lens either retracts or/and a message appears - Change the Battery pack. If the battery door is opened & closed again after slight pressing again it contnues to operate properly for sometime. Battery life - I have two batteries & are not old. My question is During assembling are there chances that the Battery springs or contacts are slightly mis-aligned & o not make contact with the attery correctly?
Very likely Take batteries out and with the eraser at the end of the pencil gently polish the contacts. Do the same with the lid contacts plate. Close it and try. If it will only work with the lid being pressed try this Take a piece of foil and lay it across the batteries then close the lid this will help pack out the contact. BE careful however if the contact plate covers 4 batteries and is in two pieces make sure there are two separate pieces and do not let them touch
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