Better start pulling connectors apart and checking grounds with your meter to determine if you're even getting power to these devices.
I'm not a fan of electrical, but it's generally something simple like a bad relay, a bad fuse, or a short in the wiring. Finding it is not the simple part.
For the record, you do not drive a FSJ. That would be a Wagoneer or Cherokee Chief from the 70's thru early 90's. You drive an XJ assuming you're driving the "regular" or "little" cherokee.
I'm back on my court mandated Rx. Other than the drool shorting out my keyboard, I'm here to help!