Flashing headlights + Battery Icon

[Foot1647]

2005 Legacy 2.5i (non-turbo)

 

I replaced the bank 1 Oxygen sensor, battery, alternator, idler pulley, spark plugs, all belts and both battery terminal connectors 2 weeks ago. Starting this morning, my wife was backing out of my parking spot, as she was turning the wheel, my auto-on headlights where flashing on and off as well as my red battery icon on the dash. It also became hard to steer I assume its from power to the power steering pump?

 

Once she drove for about 2-3 seconds the car functioned correctly again, until she left work 9 hours later and backed out of work to drive home. She stopped at Autozone (its Sunday, no mechanics open) and they tested the battery and alternator, no shorts, full voltage and no bad signals for alternator or battery. I assume it looked good because I had driven it to there, plus, they're brand new.

 

Any idea what this could be or has anyone heard of this issue? I drove the entire time with just the auto, dim lights on, with fear of full power headlights killing it and no stereo.

 

Thank you!

Edited October 14, 2018 by Foot1647
Minor corrections