PoE not working but AC power works

[Chris708]

I sent an email to support@yealink.com earlier today but haven't heard back yet so am posting the message here.

Hi, we recently purchased three CP860 conference phones.

One is having an issue where it will not power up over PoE. We have it connected via an AC power adapter and it works fine.

Our current steps to troubleshooting have been:
1. Connect Cp860 to different wall jack connected to PoE – Same problem
2. Connect CP860 directly to different PoE port in PoE switch – Same problem

Please let me know what we can do to fix / replace the phone.