you can also have a wire that is exposed and that can be making them to flicker
Probably your alternator.
The alternator is on the way out.
The headlights may flicker.
voltage regulater on the alternater is going bad
You may have a pull on your batt, or a surge.
Sounds like you need a new battery.
I had this problem and it was a bad alternator.
If the lights flicker when the vehicle is running, the alternator is on it's way out.
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...
one or more headlights don't work but others do.none of the headlights will work.high beams work but low beams don't and vice versa.lights flicker and sometimes go dim.