Video covering troubleshooting of a window defog problem. Tools used were a VOM, Amp Clamp, and one brain. The weakest link was the brain. Window "DEICE" controllers were swapped early on instead of the defog controllers which added considerable time and questioning of thought processes. Isolation of sensors was not explained very well either. But...... window heat current and voltage in action might help others to understand the system.
MD-10 ATA 30-42 Window Defog Systems
AMM Reference 30-42-01-4