12v Wiring Confirmation

[RavensFan24]

I have a 2015 Keystone Premier. I'm getting ready to purchase and install a Fantastic Fan. I checked the RV today to see if it was already pre-wired in the vent port. While it wasn't pre-wired, I did find some wires that were reachable from the port. One went to the LED light and was red and white. The other one I couldn't see what is was connected to, but it was black and white and seemed like the wire may have been a touch thicker than the red and white wire.

Based on my extremely limited electrical knowledge, I'm assuming the red and white wire is for 12v and the black and white wire is prob the 120v for the AC unit which is right near there.

Can anyone confirm or deny that this is accurate? I checked the manual and there was no real info. I know you can tie the fan into the wiring with the lights, so I'm pretty sure the red and white cable will work for my purposes, but wanted to get some confirmation if possible before I start splicing wires.

[BruceMc]

It all depends...
To find out if the red/white is 12v, pull a 12v light fixture to see if the pair has the same colors.

If so, TURN OFF ALL POWER, then snag the intended wire pair, then strip them enough to access the copper.
Turn on power - check with your voltmeter at a range for 120V AC just to ensure it is not carrying 120V. If not, then put your meter on 12V DC & check. If you have current, you are good.

Next, toggle your switch - does the power go off on that line? No? You have a good wire. Yes? then it is switched.

Have fun!

[RavensFan24]

Also, a thought I just had was regarding the light switch. If I just tapped into a wire in the ceiling, won't my fan be at the mercy of the light switch being on or off? There isn't a switch anywhere near the vent port. I'm guessing the next best option would be to go into the fuse box, which is about 5 ft away from the vent on the ceiling and about 7ft down under a pantry.