If the low beams are not working on a Peugeot 306, it is possible that the low beam headlights are burned out. If the high beam headlamps are part of the same bulb, perhaps the wrong bulbs are in the sockets. Some older cars have both the high and low beams running off the same bulb and the low beam can burn out both sides at the same time.
You use low beam headlights when you're in a town or city in any location.
On most vehicles, the low beam headlights are the outside pair of lights. This is true when the headlights are side by side. When the two sets of lights are stacked, the low beam headlights are usually on the bottom.
Low beam headlight should illuminate 85 feet of the roadway. Newer low beam headlights illuminate more of the road than older headlights.
It sounds like the low beam/high beam switch is bad. Fuses are not the problem since they are built into the headlight switch and would cause headlights to blink or not come on for both high and low beam headlights.
There are two elements in every headlight. One is for low beam (normal usage) and one is for the high beam. The high beam element tends to burn out sooner than the low beam, and it is very possible that one of your high beam elements has simply burned out. The solution is simple. Replace the offending headlight and you'll have both high beams back.
Check the grounds for the headlights.
As silly as it sounds, both low beam bulbs are most likely blown. If not, check switch in the steering column.
A reset button for headlights?
Check fuses and bulps.
The 1999 Chevrolet has a separate fuse for the low beam headlights. The low beam headlight fuse, can be found in the fuse box.