There could be a couple of reasons why the headlights won't work when the other lights do. One reason could be a blown bulb. Another reason could be a problem in the wiring.
my headlights on my 1994 pontiac gran am wont work is there something wrong with my headlight relay?
head lights wont lock in on up position
This can be due to a bad headlight switch. If it goes bad, most of the time you have no dash lights or headlights
your battery probably died
I suspect either a faulty ground circuit, or a much easier fix, faulty bulb/bulbs. You might be surprised the havoc a grounded out bulb will cause an electrical system.
Bad headlight switch
Most likely the headlight switch on the column, all the light circuits run through the switch, the switch has contacts in it that seem to wear out over time.
You may have a blown fuse.
my head lights wont come on ,,all other lights work ,,no head lights
most likely that would be a fuse
my headlights work but my taillights and dash light dont work whats wrong
there are two elements in a headlight and the high beam part may be burnt out. It happens with people who bought cheap aftermarket lights and also people who leave the high-beams on too often (like back when the headlight covers were popular)