Name one common sign that an electrical system may have a fault.

Frequent tripping of the circuit breaker is a strong indicator that there may be a fault in the electrical system. Circuit breakers are designed as safety devices that automatically shut off electrical circuits when they detect an overload, short circuit, or other issues that could lead to a hazardous situation. If a circuit breaker trips repeatedly, it usually suggests that there is an underlying problem, such as a short circuit, faulty wiring, or an excessive load on the circuit. This behavior serves as a warning sign that immediate attention and further investigation are needed to assess the safety and functionality of the electrical system.

In contrast, the other options do not typically indicate a fault in the electrical system. Having all lights on is a normal functioning scenario in many situations. Using higher wattage bulbs may simply imply that there is an upgrade in lighting without indicating a fault, as long as the circuit can handle the increased load. Adjusting timer settings involves routine adjustments for regular operation and does not represent an issue with the electrical system itself.