The answer to 'my light fixture won't turn on' is that there are several common causes, including a blown fuse or tripped circuit breaker, a faulty light switch, or a problem with the fixture itself. Symptoms may include the fixture not lighting up at all or flickering on and off.
First, check the circuit breaker or fuse that controls the light fixture. If it has tripped or blown, reset or replace it. If the problem persists, the issue may be with the light switch. Try turning the switch on and off a few times to see if it's just stuck. If the switch is working, the problem is likely with the fixture itself, such as a burned-out bulb, loose wiring, or a faulty socket. In this case, you may need to call an electrician, as working with electrical components can be dangerous for those without proper training and experience.