High resistance in the starter circuit can be checked with a/an ________ test.

• A. Voltage drop
• B. Current draw
• C. Insulation
• D. Continuity

Answer: (A)

When a circuit has high resistance, you’ll see a noticeable loss of voltage as current flows through it. In a starter circuit, the starter demands a large current, so even small resistance in cables, connectors, or switches can cause a big voltage drop. A voltage drop test directly measures the difference in voltage between the source and the load while the circuit is under load (cranking). If you find a significant drop, that specific portion of the wiring or connection has excessive resistance.

This test is more informative for this situation than the others. A current draw test shows whether the overall current is right but doesn’t pinpoint where resistance is; an insulation test checks resistance to ground in the insulation itself, not the live circuit path under operation; a continuity test checks whether a path is open or closed but doesn’t quantify resistance in a live, loaded circuit. Measuring voltage drop specifically reveals the resistance impact as the circuit operates. For example, a large voltage drop from the battery to the starter indicates high resistance in that path, which explains weak or no cranking.