Which statement about the heated mirror defogger is correct?

• A. Technician A only
• B. Technician B only
• C. Both A and B
• D. Neither A nor B

Answer: (B)

The heated mirror defogger works by a thin resistive heating element built into the mirror that warms the reflective surface to clear fog or condensation. In most vehicles, this element is powered through the rear window defogger circuit and is activated by the same rear defogger switch. That means when you turn on the rear defogger, the mirror defogger turns on as well, using the vehicle’s 12-volt electrical system and the same circuit protection (fuse/relay) as the rear window.

This setup explains why the correct statement is the one describing control and power coming from the rear defogger switch and circuit. It aligns with how the system is designed to provide fog-free visibility quickly without needing a separate control path. The other possibilities would require independent wiring or functions that don’t match typical implementations, such as a separate control for the mirror or defogging behavior that doesn’t rely on the rear defogger circuit.