What must a crew member do to test a spring switch before a train or engine makes a facing point movement over it?

A crew member must test a spring switch before a train or engine makes a facing point movement by lining the switch over and back by hand and examining the switch points. This procedure ensures that the switch is properly aligned for the movement and confirms that the switch points make good contact with the stock rails, which is essential for safe train operations. Manually lining the switch helps to identify any potential issues such as debris or mechanical failure that could compromise the switch's functionality.

The other options do not specifically address the critical safety procedure needed to verify the proper functioning of the spring switch. While checking the train's speed before approaching the switch is important for overall safety in train operations, it does not directly ensure the switch is lined correctly. Consulting the train dispatcher for instructions can be part of operational procedures but is not a method for testing a switch. Ensuring that the block signal is displaying green indicates that it is safe to proceed, but again, it does not guarantee that the switch is in the correct position for a safe passage. Therefore, the focus on directly testing and inspecting the spring switch aligns perfectly with the safety protocols necessary for train operations.