If you are getting bright headlights at both high and low beams it doesn't sound like there's a bad wiring connection - you're getting full voltage and current - or as much as the std. setup allows. The high and low beams are switched on/off by the relay the other guys are referring to. The high beams are switched on when the small brown wire going into the relay is grounded via the turn signal/beam switch on the left of the strg column. When you remove that ground by flicking the lever a second time, the high beams should instantly turn off (you indicate that this happens) and the relay should just as instantly switch the lows on. So I'm guessing it's a sticky relay. Try getting someone else to work the high-low lever, and when they switch to low, give the relay a good rap with a plastic screwdriver handle, and see if that brings the low beams immediately on.