701c think pad battery operation

[walt belsito]

hi ;

i have a 701c .

this is the 3 rd new battery i put in it .

here is the problem ;

it works fine on a external power pack .

with a fully charged battery installed ,

you get a quick flash of the lights

AND 3 quick beeps .

then it goes off .

any ideas ?

WALT, waterbury , ct .