2008 Chevy Impala low beam headlights not working ok. Passenger side works sometimes if switch is turned to manual. Driver side out. Bulbs replaced...same problem. Fuses under hood checked...all OK (including 15amp relay). Highfbeams OK in manual position/don't work if switch is in AUTO position. Thinking it maybe multifunction switch. Dome on dash for daylights clear/uncovered. Any thoughts?

 

Why not check with a forum that is dedicated to Impalas?

 

Multi switch, ground wires, damaged connections or harness, faulty bulbs or sockets.

 

I'm sure that the entire system from wiring, switches etc. is going to be different than the HHR.
As suggested, maybe try a forum that deals with Impalas like this one: Chevy Impala Forums

 

If it's got a bowtie we'll have a few suggestions!