[Stingray70]

Another easy thing to check is the headlight conduit connectors. When I got my car the incorrect bullets were on the wiring harness. They were making contact with one another in the round plastic piece (at the back of the headlight) causing all sorts of bizarre lighting combinations.

I took the connectors apart, separated the wires and checked each one with a voltmeter. I would have sworn it was a bad switch but it wasn't. In my case I installed the correct bullets and replaced the plastic connector inserts.