an even simpler and less expensive device than a wire map tester

an inexpensive, battery-powered light with a probe at one end and a wired clip at the other

a simple device which provides an audible indication when a sufficiently low resistance is applied between its input probes

An electrical tool used to identify and diagnose a circuit as either open or closed.

A simple, battery-powered tool that indicates whether an electrical circuit is complete or incomplete by lighting or buzzing when you touch its two probes to the wires.

Test device for electrical circuit

A battery-powered continuity tester has an alligator-clip lead and a metal-tipped probe. When the power is turned off, it can detect shorts in cartridge fuses, switches, and sockets. Home Improvement Encyclopedia

A device that tells whether a circuit is capable of carrying electricity

A continuity tester is an item of electrical test equipment used to determine if an electrical path can be established between two points; that is if an electrical circuit can be made. The circuit under test is completely de-energized prior to connecting the apparatus.