The serpentine belt gets powered by the engine as it turns. The belt runs your alternator, air conditioning, and power steering pump. On certain vehicles, it also runs the water pump, radiator fan, and power brakes.
If the serpentine belt breaks your battery won’t last. The car can not run on the battery. If this happens the engine could overheat before the battery dies. Your steering and braking could also be affected.
Checking for belt cracks no longer applies to newer belts, it depends on the belt thickness. We have new tools to measure the depth of the belt.