Switch Assembly

Using a circuit tester, check there is continuity between S terminal and M terminal, and between S terminal and ground. Also, check that there is no continuity between M terminal and B terminal.

Courtesy of SUBARU OF AMERICA, INC.

Terminals Standard 

Terminal S - terminal M 1 Ω or less

Terminal S - Ground 1 Ω or less

Terminal M - terminal B 1 MΩ or more