Switch Assembly

Return spring check
Make sure the plunger returns to its original position immediately after pressed-in then released.

Fig 1: Checking Return Spring
Courtesy of SUBARU OF AMERICA, INC.
Magnet switch continuity test
Be sure there is continuity between the terminals S and M, and between terminal S and ground. Use a circuit tester.

Also check to be sure there is no continuity between terminal M and B.

Terminal/Resistance:

S - M/1Ω or less

S - Ground/1 Ω or less

M - B/1 MΩ or more

Fig 2: Checking Continuity Between Terminals S And M, And Between Terminal S And Ground
Courtesy of SUBARU OF AMERICA, INC.