shouldn't the fuse system stop a motor short or motor fail on blower motor? on 2010 Ford F-150

I had my truck running for two minutes when I smelled something burning. I realized the A/C wasn't working and opened the hood. saw the compressor working fine. Got back inside, shut off the A/C system and saw smoke coming out of the dash, grabbed a shirt but it was too hot to put out the hot melting plastic. So luckily I had an extinguisher and put out the fire in the dash and floorboard. So why didn't the fuse system prevent this?

by in Orem, UT on June 30, 2013
2 answers 1 comment
ANSWER by , June 30, 2013
Any add on equipment or accessories at all?
COMMENT by , June 30, 2013
All stock, just 98 degree day and white truck in color with window shades, as averages go the outside heat shouldn't have been a factor either
ANSWER by , July 01, 2013
poss under warranty at dealer