The phone features a broken screen and a deformed housing. Get a new display assembly installed and test. The phone turns on normally. Both the front camera and the rear camera work normally. WiFi also functions well.

Go to Sounds & Haptics > Ringtone. Select a default ringtone and there is no output sound. But the sound works fine with headphones in.

The preliminary judgment is that the audio circuit is in normal condition. It's just that the bottom speaker is not working. Remove the display assembly and disconnect the battery.

Disconnect the charging port flex cable. Run diode mode measurement of Pin 1 and Pin 45 of the DOCK connector. The measured value is 5, which indicates that the bottom speaker is in normal condition.