If the LOCK is NEW:
The Coin Cell insulator may have not been removed when installed.
Pull the Mylar insulator from the coin cell battery housing per the installation instructions.
The coin cell battery is low, less that 2.7 VDC. A new coin cell battery should read at least 3.0 VDC.
Install a new coin cell battery, The part number of the coin cell battery used in the AD and CO series locks is: CR2025
For equivalent batteries see 68659
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