The alternator is on the way out.
Probably your alternator.
voltage regulater on the alternater is going bad
The headlights may flicker.
If the lights flicker when the vehicle is running, the alternator is on it's way out.
Sounds like you need a new battery.
I had this problem and it was a bad alternator.
You may have a pull on your batt, or a surge.
When a cars headlights, AC, and radio are losing power, it is possible the alternator.
you probly just have a bad conettion just take it to your local shope it shouldn't be over 50 dollars to fix.
Flickering headlights on a 2005 Silverado may be caused by faulty relays or electrical wiring. The fuses and lights may also be going out.
Loose wires, loose bulb, loose switch. Or maybe its because you live on a really bumpy road and it only looks like they flicker...