It is the Toyota drive and serpentine belts on the front side of the engines that make it possible for the engine to maintain a constant operating temperature, produce electricity, and assist your steering. The belts are made of a reinforced polymer, are circular in nature, and have several rows of grooves on the inside. These grooves exist so they can be placed in the many different pulleys on the front of your Toyota engine. This is how they can supply the necessary centrifugal power to the many accessories required of a modern power plant under the hood of a vehicle. The pulley that is the source of power for the centrifugal rotation is the harmonic balancer located in the center bottom of the front of the engine. It is directly connected to the crankshaft of the engine. As long as the engine is running, power will be available for the drive or serpentine belts to take advantage of so it can be utilized when your Toyota is operational. The differences between the Toyota drive and serpentine belts are small but significant. The drive belts are not as wide and there are more of them. There is only one serpentine belt that can be on an engine at one time and they are two to three times wider than the drive belts. The similarities of the drive and serpentine belts include they are circular and have four flat edges. The material they are made out of are also the same, a reinforce polymer. Because the belts on your Toyota are made of the same material they will have the same wear patterns that include cracking and fraying when they get old. When these conditions on a belt are seen, they should be replaced before they break leaving the occupants of the vehicle stranded on the road.