Self-Powered Test Lamp

This lamp is a pencil-shaped unit with a self-contained battery, a 1.5-volt lamp bulb, a sharp probe, and a ground lead fitted with an alligator clip.

This test is used mainly for testing components that are disconnected from the vehicle voltage supply. The powered test lamp is also useful for testing suspected high resistance points in a circuit such as connectors and ground circuits that are corroded or loose.