Same problem on my 03 LX
Searched the forum here and found this: Headlight Buzzer
Just take off that light switch in the door jam, try to get the switch
out with the wires attached. That rubber covers the switch holder,
I was able to press the switch back into the holder, it only goes one
way. Check driver and passenger side.
TaDa! Twenty minutes and zero dollars. No more dead batteries.
Thank you CivicForums.com and all the smart people who post here!