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The C:31:23 error code indicates that the camcorder has detected an issue that may require a power reset. Check if the battery of the Camcorder is fully charged.
To power reset the Camcorder, follow the steps as mentioned below. 1) Turn off the camcorder. 2) Remove the battery or disconnect the AC power adapter for 60 seconds. 3) Insert the battery or reconnect the AC adapter.
If the issue still persists, you can try resetting the Camcorder to factory default settings. All the personal settings including the date and time return to their default settings.
To reset the Camcorder, press the RESET button using a small pin pointed object for 2-3 seconds.
If this does not resolve the issue, then the Camcorder may require service. You can initiate the service request for the Camcorder from the following link: https://eservice.sony.com