Driving a car with a malfunctioning air conditioner is an uncomfortable and unhealthy experience, especially if the temperature is high. You need to be on the lookout for signs of failing AC belt so that it doesn't snap and leave you without AC when you need it most. Here are some of the common signs that should tell you the belt is up for a replacement:
Noises from the AC
The AC belt is made from rubber, which is subject to degradation due to temperature changes and friction. Both forms of deterioration cause cracks and tears on the AC belt. The cracks cause rough patches on the surface of the belt, which creates bumps and noises as the belts turn over the pulleys. A worn AC belt may also be longer than the pulleys are meant to handle. That will also generate noise when the belt slips from the pulleys due to poor grip.
Note that you need to diagnose the noises to confirm that they are caused by damaged AC belts. Don't assume that belt damage is the cause because other things, such as debris or water on the belt, may also cause similar noises.
Malfunctions in Connected Systems
The AC belt isn't exactly an AC belt – that is, the AC isn't the only thing it controls. Technically, it is known as the serpentine belt, and it controls multiple parts of your car. Therefore, a malfunction in any of these related or connected parts all signals that the belt is damaged and is due for a replacement.
For example, in some vehicle models, the windshield defroster is connected to the air conditioning system. if that is the case with your car, then the AC compressor needs to be operational for the defroster to work. Since it is the AC belt that controls both the compressor and the defroster, a malfunctioning defroster should tell you that the belt is malfunctioning.
Signs of Physical Damage
A physical examination of the AC belt may also reveal if it is failing and needs to be replaced. Signs of physical damage include cracks on the belt, bruises or abrasions on the belt, missing pieces on the belt, and an unusually long belt, especially if the belt was of the right size when it was fitted.
As discussed above, some of these signs may point to other forms of malfunctions. Therefore, consult a mechanic, like those at Modern Auto Air, for a professional diagnosis before buying a belt for DIY replacement.