Why can't TV detect MHL™ (Mobile High-Definition Link) device automatically?
MHL™ (Mobile High-Definition Link) device is detected automatically when the cable is inserted.
Please turn On the Auto Input Change by select Set-up → BRAVIA Sync Settings.
When Auto Input Change (MHL) is set to On, the TV automatically switches to MHL mode when MHL-compatible device is connected to HDMI IN/MHL jack.
The availability of Auto Input Change(MHL) depends on whether the MHL-compatible device can support this feature.