I have an AP 150 (1700412E1) which has been powered via AC adapter for a few years. I attempted to remove the AC adapter and power the AP via PoE. The AP wouldn't light up. I tried another AP 150 that I had and it came up right away on the same cable. Did Adtran produce two models of the 150 at any time? One for AC power / One for PoE?
Thank you for asking this question in the support community.
To my knowledge, ADTRAN did not produce any NV150s that required external power. Based on your troubleshooting description, it appears you proved the switchport and cable. If you would like to perform additional troubleshooting on the unit I would suggest trying the AP on a different switchport or different unit.