It's unlikely the wires themselves are bad. You're going to have to troubleshoot it to determine the cause of the problem. In doing so, you run the risk of compounding the problem. Even if you don't damage it further, any signs of disassembly may be enough for the dealer to void warranty coverage on it.
Therefore, since this is a new rig, under warranty, I wouldn't fool around with it.
Nonetheless, the most likely problems are:
1. Tripped breaker, check your 12v breaker panel.
2. Blown fuse at the fan (if there is one). If this is the issue, why did it blow?
3. Faulty wall switch, if you have one.
4. Loose power or ground connection at the fan.
5. Faulty switch/control at the fan.
6. Failed motor.
All of these, except #1. will require some degree of disassembly, poking around with a multimeter and possibly disconnecting a wire or two.
I applaud you for wanting to DIY and, although it's not that complicated, it does require some skill in using a multimeter, knowledge of how the fan is designed and familiarity with 12V circuits.
Just let the dealer take care of it, and, while you're at it, make a list of anything else that isn't working properly. By the time your warranty has expired, you'll know a lot more about your rig and can join the rest of us DIYers.
2002 Itasca Suncruiser 35U