to me, a serpentine belt is any belt that drives multiple things
and snakes around pulleys and idlers
The word says it all, serpentine..
It can be a ribbed belt
it may be used for timing
On most cars you'de have a timing belt and seperate timing belt
But it's not mutually exclusive..And there's no real law that prevents using one for timing either...or requires it to be a toothless belt.
it just needs to snake around and drive several things...
for instance on a 928, the timing belt is a serpentine belt in it's own right
It drives 2 cams, water pump, oil pump... and snakes around quite a bit.
