The high low beam switch replacement requires removing the steering wheel (disarming the steering wheel air bag where applicable special precautions are necessary or the air bag may deploy!). Initially see if you have power on the red/white at one head light red/green wire at the other head light if you have circuit is OK bulbs are bad. fuse 10 and 11 (both 10 Amp) should have power when the headlight switch is on low beam. White going into what Honda call the combination switch (headlight switch) should have power all the time, the red/yellow wire out of the headlight switch should be live in low beam position if switch is OK.