Researched the internet and watched a lot of Youtube videos. Disassembled and tested individual defroster components and concluded it was a bad control board.
Purchased it here because they had the specific part for my model, certified factory part and guaranteed fast shipping in my area.
Got the part fast, popped it in and we're back in business.
Research and diagnostic time took 3 hours or more. The actual part replacement was 5 minutes. Programming the new board and retesting took 30 minutes.