The first thing I think of deals with the TIPM (totally integrated power module). I have run into this issue before. There are several tiny pins at the connectors and oftentimes they break or corrode.
What I need you to do is this: At the lamp connector, I need you to check for power. If we have power (12v), I need you to reconnect the socket and back probe the power supply and see if there is power loss. That would indicate a bad connection for a number of different possible reasons.
I attached the wiring schematic below for you to review. It is the schematic for the headlamp circuit. I highlighted the wires that are related. For example, when the right low beam doesn't work, I highlighted the wire that should power it. The same with the high beam on the left. Here is a link you may find helpful:
Try this and let me know the results.
See pics below.
Images (Click to make bigger)
Wednesday, June 9th, 2021 AT 9:59 PM