Which component transfers high electrical current from the battery to the starter motor when energized?

Which component transfers high electrical current from the battery to the starter motor when energized?

• A. Starter solenoid
• B. Y strainer
• C. Radiator Pressure cap
• D. Coolant temperature sensor

Answer: (A)

When starting an engine, you need a switch that can carry a very large current to the starter motor without routing that power through the ignition switch. The component that does this is the starter solenoid. It acts as a relay: a small current from the ignition switch energizes the solenoid’s coil, which pulls a plunger to close high-current contacts. That opens a direct path from the battery to the starter motor, delivering the heavy amperage needed to crank the engine. At the same time, the solenoid can push the starter gear into mesh with the flywheel so the motor can actually turn the engine over. The other parts listed aren’t involved in delivering high current to the starter: a Y strainer filters fuel, a radiator pressure cap controls cooling system pressure, and a coolant temperature sensor monitors engine temperature. So the starter solenoid is the component that transfers the high electrical current from the battery to the starter motor when energized.

When starting an engine, you need a switch that can carry a very large current to the starter motor without routing that power through the ignition switch. The component that does this is the starter solenoid. It acts as a relay: a small current from the ignition switch energizes the solenoid’s coil, which pulls a plunger to close high-current contacts. That opens a direct path from the battery to the starter motor, delivering the heavy amperage needed to crank the engine. At the same time, the solenoid can push the starter gear into mesh with the flywheel so the motor can actually turn the engine over. The other parts listed aren’t involved in delivering high current to the starter: a Y strainer filters fuel, a radiator pressure cap controls cooling system pressure, and a coolant temperature sensor monitors engine temperature. So the starter solenoid is the component that transfers the high electrical current from the battery to the starter motor when energized.