A power window switch is being tested. Which statement accurately reflects the continuity test?

• A. The switch must be open when testing for continuity
• B. A reading of no continuity indicates a properly operating switch
• C. Both A and B are correct
• D. Neither A nor B is correct

Answer: (D)

Continuity testing checks whether a complete conducting path exists between two points. For a power window switch, you want to see continuity when the switch is in the position that closes the circuit, and you should see no continuity when the switch is in the position that opens the circuit. The statement that the switch must be open when testing for continuity isn’t correct because the test’s purpose is to verify a closed path in the operating position, not to require it to be open. Likewise, a reading of no continuity does not indicate a properly operating switch—usually it means the circuit isn’t closing when it should. So, you should test both states: continuity when closed, and no continuity when open.