Car Battery Problem on a 05 Chevy Cobalt.?

[G_baby]

Battery losses charge easily. I've change battery and replaced alternator yet the battery still losing charge. I've have installed a car stereo and headlights.
check light has remained on since i've replace the alternator

 

[Cruiser]

Check your glove box light or trunk light to see if they are going out. Something is staying on in the vehicle.Some cars have a light under the hood also. A cell phone charger can drain a battery if left for 24 hours or more.Satellite radios too.