No low beams when headlights are on but low beams work when switch is on parking lights.

Well, it is either the multi-function switch or the "smart" junction/fuse box. To test which it is, you need a piece of wire connected to a good ground. It needs to be long enough to reach the smart fuse box under the dash on the left side. Find a blue wire that connects to terminal twenty one, this wire also connects to the multi-function switch so you could trace it from there if needed, just be sure it connects to terminal twenty one. Turn the key on, turn the headlights to the headlight position, No low beams. Touch the wire jumper to the blue wire. If the lights come on now the multi-function switch is bad. If not then it is the "smart" junction box (it has a computer that turns on the lights and dims them inside it).

If the wiring diagram is correct the wire you want will be in the connector I drew the arrow to. It's on the back of the box. There should be enough wire to remove the screws and pull the box out to access the connector. Try wiggling the connector first to scrub the terminals. Bad connections are very common. If they come back on great. If not then it's time to test.

Just be sure you have the correct wire, the wrong one could make a costly error.

I HATE them myself. Take your problem for instance. They are switching the headlights for crying out loud, do you really need a custom hidden part to do what a simple dimmer switch did for 50+ years? Every time I see some of this stuff a line that Jeff Goldblum says in Jurassic Park pops into my head, "Your scientists were so preoccupied with whether or not they could, they didn’t stop to think if they should".

You're very welcome.

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