So last week my passenger low beam was not as bright as the other side. I jiggled it to see if I had a bad connection. I turned on the high beams and it went out entirely. I just bought the light back in February. I used my multimeter to check the light and to check to see if there was any power to the passenger headlight connection. I got nothing. My question is where do I start looking to find the culprit 

If you think the bulb is good, check the main connector on fender top drivers side. Make sure it's clean and tight.

If I understand you correctly it’s located on the top side against the firewall? I checked this cluster of wires. It looks normal. I am going to remove some of the obstructions and investigate further thanks.

The first thing I’d try is swapping the low beam bulbs with each other. If the problem follows the bulb, that’s your culprit. 

While you’re swapping bulbs, look at the plugs and see if there’s corrosion. That’s a possible source of trouble.

If the problem stays on that side regardless of which bulb is in there, I’d start examining the connector and wires from the headlight and working back. A probe like a safety pin that you can poke into a wire to check voltage without cutting it is useful. 

I had a similar problem too. It was the bulb. R&R'd with a new one and All Was Well.   ???

Best of luck.

Steve