The issue you're experiencing with your Toyota Corolla's AC could be caused by a few different factors. While a serpentine belt can affect the performance of various components in your car, it is not directly related to the functioning of the AC system. Here are a few potential reasons for the problem you described:
Condenser issue: The condenser is responsible for cooling the refrigerant in your car's AC system. If it is damaged or clogged, it may struggle to cool the refrigerant effectively, leading to reduced performance at higher speeds.
Cooling fan problem: The cooling fan plays a crucial role in maintaining proper airflow through the condenser. If the fan is malfunctioning or not operating at higher speeds, it may result in inadequate cooling, causing the AC to stop working or perform poorly.
Low refrigerant levels: If your AC system has low refrigerant levels, it may struggle to cool the air properly, particularly at higher speeds when there is increased demand for cooling. This could be due to a leak in the system, which should be inspected and repaired by a qualified technician.
Blockage in the air intake or cabin air filter: A clogged air intake or dirty cabin air filter can restrict the flow of air into the AC system, affecting its performance. It's worth checking these components and cleaning or replacing them if necessary.
Given the symptoms you described, it's recommended to have a professional mechanic inspect your AC system. They will be able to diagnose the exact cause of the issue through a thorough inspection and testing of the various components. This will help ensure an accurate diagnosis and proper repairs to restore your AC system to optimal working condition.