I've been having issues with my interior and exterior lights flickering in my 2013 JKU. They only flicker when the engine is running and flicker at the rate in which the engine idles. I called the dealer (to avoid bringing it in for something silly). They told me to check the draw in the alternator and said it may be drawing to much power. I'm a newbie to tech so, how do I exactly "check the draw" to the alternator? What am I looking for? How will I know if this is the issue with my JKU?

Thanks guys.