Why does the belt squeak when the air conditioner is turned on in a cold car?
2 Answers
It may be because the belt is slipping on the generator, causing intense friction and vibration between the belt and the pulley, resulting in a noise at a certain frequency. Here is the relevant content introduction: 1. Main reason: The main reason for belt slippage is belt looseness or aging. Factors that can cause belt looseness include improper adjustment of the belt tensioner or insufficient tensioner elasticity. In this case, the tension of the belt tensioner should be adjusted first. If there is no effect, the tensioner should be replaced. 2. Reduced friction: Belt aging mainly refers to the belt gradually hardening and losing elasticity during long-term use, reducing the friction between the belt and the pulley. In this case, the belt can only be replaced.
My car sometimes makes a squealing noise from the AC belt right after a cold start when I turn on the air conditioning, which is quite annoying. This issue is mainly caused by a loose or aged/worn belt. In cold weather, the belt material hardens and loses elasticity, and when the AC compressor load increases, the belt tends to slip and make noise. When I used to work on cars myself, I tried checking belt tension—a simple method is to press down on the middle of the belt with the engine off; if it depresses more than half a centimeter, it's too loose and needs adjustment of the tensioner pulley screw or replacement. Cracks, dirt, or oil stains on the belt surface can also cause noise, and cleaning the grooves might help. Not addressing it promptly could affect other components like the water pump or alternator, increasing repair costs. After I replaced the belt myself, the noise disappeared, but if you're not very car-savvy, it's safer to have a professional mechanic check it. Regular maintenance can extend its lifespan and keep your car running smoother and more fuel-efficient.
