Headlight bright/dim switch does not work

[Alex Ethridge]

I have a 2003 Sienna and the switch that changes from dim to bright lights does not work at all. I think they are stuck on dim. Pushing the controller downward as one would do to change from dim to bright nor pulling it upward has no effect whatsoever.

I have checked the bulbs by putting them both into my '01 Sienna and they work properly there.

Is there possibly a relay somewhere that might be the culprit? If not, then what?