What can cause voltage drops in an automotive circuit?

Voltage drops in an automotive circuit can occur due to a variety of factors, with corroded connections being a primary cause. Corrosion at the connection points impedes the flow of electricity, resulting in increased resistance. When resistance increases, the voltage drops across that connection or wire, which can lead to insufficient voltage reaching components downstream in the circuit. This can manifest as dimming lights, poor performance of electrical components, or complete failures in some cases.

In contrast, new wiring typically does not contribute to voltage drops; rather, it should offer lower resistance if properly installed. Properly rated fuses are designed to protect the circuit from excess current and do not inherently cause voltage drops. Unused circuits, while they may not affect actively used circuits, also don't contribute to voltage drops in a direct sense. Therefore, the presence of corrosion is a significant factor impacting voltage levels in automotive circuits.