What tool would be most effective in measuring high current levels in a vehicle circuit?

A clamp meter is the most effective tool for measuring high current levels in a vehicle circuit because it allows for the practical measurement of current without the need to disconnect the circuit. This is particularly beneficial in automotive applications where circuits can be complex, and interruptions can lead to issues with the vehicle's electronic systems.

Clamp meters work by detecting the magnetic field around a conductor and providing a direct reading of the current flowing through it. This non-invasive measurement method makes clamp meters ideal for diagnosing electrical issues or evaluating current draw in various components without exposing wiring, reducing the risk of damage or safety hazards.

While a voltmeter is suitable for measuring voltage, it does not measure current directly. A test light can indicate the presence of voltage but cannot provide an accurate reading of current levels. A battery tester is primarily designed to assess the condition and capability of a battery rather than measuring current in live circuits. Thus, the clamp meter stands out as the most efficient and safe choice for high current measurement in vehicle circuits.