There is no alarm sound warning for abnormality of tires.
Check if the device is in silent mode or if the volume has been turned to lowest setting.
Certain models of iPhone will not give audio alerts if connected to multiple Bluetooth devices
simultaneously.
For additional troubleshooting, call ASA Electronics Technical Support at 1-800-688-3135, email
inquiry@asaelectronics.com or visit our website https://in-command.net/tpms/