Cisco BEKEM Manual page 15

Cisco IP Phone Key Expansion Module
Key Expansion Module Does Not Go Through the Normal Start Up Process
• Power over Ethernet (PoE) doesn't meet the required power-supply.
• Connected number of key expansion modules exceed maximum "Number of Units".
Solution
• Change the phone to use the same type of expansion module.
• Check the PoE the phone connected to.
• Check if the unit number is bigger than the "Number of Units".
Cisco IP Phone Key Expansion Module
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