Bulb and Fuse Tester
The Bulb Tester is designed to fit most miniature light bulbs. Place the bulb in the tester making sure the two thin wires of the bulb firmly touch the metal inside the bulb tester. A good bulb will illuminate when its wires touch the contacts of the Bulb Tester.
The Fuse Tester is designed to check 3 amp fuses which are supplied with most miniature light sets. Those fuses are located in the plug of the light set. Place the fuse in the Fuse Tester on top of the LightKeeper Pro, making sure the fuse touches the metal contacts on both sides. If the fuse is good, the red LED on top will illuminate. Please be aware that blown fuses are usually indicative of an overloaded circuit or a larger problem.