notebook wont power up

i have Acer Aspire 9300-5005 AMD Turion 64 X2 TL-50 1.6GH

when i hold down the power button

the battery light blinks for about 1 to 2 seconds then goes off

there is no capslock or other lights that come on
the battery is plugged in and so is dc adapter etc
even if the battery was broke it still should start up
any ideas guys