How can I reprogram my PCM myself

What is your question?

Every replaced the alternator battery and starter I've lost power to my low beam headlights at random I have my ABS light and traction control light come on my battery don't charge and it loses all power once the battery dies

What makes this problem better or worse?

It generally has other issues such as the ABS and traction control when it's cold

How long has your 2008 Chevrolet Cobalt had this problem?

Just recently