Do I need to use P.ANT or configure antenna power somehow?

The Z-N528 features phantom power supply for DAB antennas, which is set to ON as factory default and can be switched ON or OFF individually.

The Z-N528 does not come with internal phantom supply for FM antennas. Vehicles with FM antenna system that require a phantom power supply need to foresee the purchase of a suitable FM antenna supply adapter. The supply adapter will usually get  connected to and controlled via P.ANT cable of the device.