What instrument is used to verify a ground path under load by measuring voltage drop?

• A. DVOM to measure the voltage drop
• B. Ohmmeter
• C. Battery tester
• D. Test light

Answer: (A)

Measuring voltage drop along the ground path under load shows how good the return path really is when current is flowing. A digital volt/ohm meter (DVOM) lets you measure the actual voltage difference across the ground conductor while the circuit is energized, so you can see how much voltage is lost as current travels back to the battery or chassis. If the drop is very small, the ground is solid; a larger drop points to resistance from a loose connection, corrosion, or an undersized wire.

The other tools aren’t suited for this purpose. An ohmmeter measures resistance with power removed, so it won’t reveal how a circuit behaves under operating load. A battery tester checks the health of the battery, not the integrity of the ground path. A test light shows only whether voltage is present; it doesn’t quantify the drop or pinpoint issues along the path.