This variator belt drives the air-conditioning compressor from the engine's accessory drive system. It transmits power through the pulley system to maintain compressor rotation for cabin cooling. A worn or slipping belt reduces compressor speed, leading to insufficient refrigerant circulation and warm air output. The belt is manufactured to the original profile and tooth pitch, which keeps tension within the design range of the automatic tensioner. On installation, verify the belt tracks correctly on all pulleys and that the tensioner moves through its full travel.