WV Chris observed correctly, and pointed out the obvious.
Ind Chris is making assumptions and jumping to conclusions. Stick to the facts and then you can figure out the why.
You know where there was heat.
You know no fuse opened, but you do not know the circuit? So maybe its not fused? or has a CB? or ?
Certain bulbs stopped working - so now you can figure out the circuit. The bulbs are not damaged, therefore they did not draw excessively high current.