The answer to 'my electrical panel won't turn on' is that there could be several common causes, such as a tripped circuit breaker, a faulty breaker, or a problem with the main power supply. The symptoms may include complete loss of power or certain circuits not working, and the solution will depend on the underlying issue.
If the panel is not receiving any power at all, the first step is to check the main breaker or disconnect switch. If it has tripped, simply reset it. However, if it trips again, there may be a short circuit or overload in the electrical system that needs to be addressed by a professional electrician. They can inspect the panel, identify the problem, and make any necessary repairs or replacements.