Some embodiments of the invention provide a method for a PIM (passive intermodulation interference) detection RAN (radio access network) application deployed across one or more RICs (RAN intelligent controllers) for detecting PIM in a RAN including multiple RAN base stations for servicing multiple users located across multiple regions, each region including at least one RAN base station. The method is performed for a particular region serviced by a particular RAN base station. The method detects (1) high uplink noise for the particular region and (2) antenna imbalance for the particular region. Based on said detection, the method determines whether high KPI (key performance indicator) impact is detected for the particular region. When high KPI impact is detected for the particular region, the method generates a PIM alert to notify an operator of the particular RAN base station that services the particular region that PIM is detected for the particular region.