On our 2002 Islander, these wires to the bow were not connected at either end. The aft end of the wires were coiled up and stuck up under the console, in the outboard corner. Had to use a light, spot them, then pull down.
When this was all the "pre-wire" I found, I asked the factory where they go the power from. They indicated that they simply tapped in to the normal power under the helm console.
I found this to be a poor response, or at least an accurate response to a poorly-designed system. The main feeder breaker aft for the power to the console is only 40-amps, and the wiring is designed for that load. To add a windlass, with a 25-amp or 40-amp breaker of its own, to that distribution is just an invitation to have your electronics all restart when you use the windlass.
I installed a Horizon 500, and it has a 25-amp breaker. I installed a completely separate feed from the house bank aft, with a 40-amp breaker aft, to bring power forward. The windlass breaker and control switch are at the helm, and then I used the pre-installed wiring from the helm to the bow to supply the windlass.
Here is a photo that shows the breaker just under the lower edge of the console, below the switch panel. The control toggle switch can be seen in the storage bin to starboard, just forward of the cup holder. (Note: Old photo, before the repower in 2005 and the two major electronics upgrades since then as well.)