What is one sign of a faulty electrical cord?

A frayed or exposed wiring is a significant sign of a faulty electrical cord as it directly poses a risk of electrical shock. When the outer insulation of a cord is damaged, it exposes the inner wires, which can lead to short circuits, increases in electrical resistance, and may ultimately result in dysfunction or fire hazards. This condition is particularly dangerous because it can allow electricity to escape, which can create a shock hazard for anyone who comes into contact with it. Recognizing this sign is crucial for maintaining safety while working with electrical equipment in automotive and other environments where electrical cords are used.

The other aspects mentioned, such as the brightness of the light when plugged in or unusual sounds when the cord is moved, may indicate different issues but are not as definitively indicative of a faulty cord as signs of physical damage. The length of the cord does not contribute to its safety functionality directly, except in very specific scenarios related to reach and power requirements. Thus, identifying frayed or exposed wiring as a clear sign of potential danger reinforces the importance of visual inspection in electrical safety practices.