A blown fuse will appear ___ on a thermal scan.

• A. As a cooler temperature
• B. As a hotter temperature
• C. Brighter in color
• D. Darker in color

Answer: (A)

When you’re using a thermal scan, temperature differences reveal where current is heating components. A fuse that has blown opens the circuit, so no current can flow through it. Without current, there’s little to no heat generated in the fuse, making it cooler than surrounding parts. In the camera’s heat map, that cooler reading translates to a cooler temperature and often a darker area compared to nearby energized components. If the fuse were still conducting or shorted, you’d expect it to run hotter due to I²R heating.