What position should the Main Battery Knife switch be placed prior to starting the engine?

What position should the Main Battery Knife switch be placed prior to starting the engine?

• A. Open
• B. Closed
• C. Off
• D. Standby

Answer: (B)

Power must flow from the battery to the starter and ignition to crank the engine, so the main battery knife switch needs to be in the closed position. When closed, the circuit is completed and the battery feeds the starter and essential electrical systems, allowing the engine to start. If the switch were open or off, the battery would be isolated from the system, preventing cranking and starting. Standby isn’t typically used for a full start because it doesn’t provide the necessary full-power connection.

Power must flow from the battery to the starter and ignition to crank the engine, so the main battery knife switch needs to be in the closed position. When closed, the circuit is completed and the battery feeds the starter and essential electrical systems, allowing the engine to start. If the switch were open or off, the battery would be isolated from the system, preventing cranking and starting. Standby isn’t typically used for a full start because it doesn’t provide the necessary full-power connection.