I am wiring up a sound bar in my 2021 800Ex and came across these two wires under the hood.  What are they used for and can I use the one with two wires for my sound bar power? I am also putting in a switch in the for it

[2015 Z Force 800 53/Trail EPS]

No clue. Many wiring changes after 2018. You will need a new wiring diagram most likely. I can give you one for the pre-2018s and it may have those but...don't hold your breath. Really should consider using the ACC circuit or run one yourself using a relay triggered by that same ACC line. It's keyed and won't effect any other systems.

https://documentcloud.adobe.com/link/track?uri=urn:aaid:scds:US:6ddb637f-0c5d-470d-a337-3a14cc6484a6

It doesn't matter. It should have a proper circuit with it's own fuse and proper wire gage for the application. Adding extra draw on an existing circuit invites overloads and potential fire risks.

[2015 Z Force 800 53/Trail EPS]

Adding extra draw on an existing circuit invites overloads and potential fire risks.

X2. Well said. These system circuits are designed for what they have on them only..nothing else.

Got it, thanks for the replies

Circuit overloads are a valid concern. Especially if it is a high watt sound system. The following is just what I did and I am not openly recommending it, I made a 8 gauge wire power takeoff that directly connects to the positive battery terminal with a fuse holder before anything attached to it. Always fuse any circuit that comes directly off a power source. Just my 2 cents (25 cents after inflation).

As I am an electrical engineer on tour buses and motor homes and such. I would fuse both ends. One within 13 to 18 inches of battery and one the same from the load. This will prevent and fire possibility due to a short. The one by the battery should be sized according to wire size and one by the load should be whatever size fuse the product asked for. I always run larger wire than products ask for. And upsize wire 1 size for about every 25 ft to account for voltage drop.