the turn signal not working is a common problem, its the flasher relay and it has a hair line crack that keeps it form working.
you can fix it yourself or buy a new one and pop it in, but can only get it form the dealer this is the parthttp://www.justforjeeps.com/flasher.html
its in a tight to get to but you can get it.
first remove the fuse cover on the bottom left, it pops off.
then you have to remove the small plastic that is above the the steering wheel, it pops right off.
then you have to remove the big plastic piece under the steering wheel.
the relays are located above the fuses so get a flashlight, put your head on the floor and look up. the flasher relay is on the top row in the middle,its the one that stick out the most. can wiggle it out and if needed use a pair of needle noise pliers to wiggly it a bit to start it. its the one label combination flasher at the top and the relays at the bottom are what you normally see after you pull that small cover off
now you have it out and you can see 2 push tabs on the sides, use a small flat screwdriver to pop the cover off. now its time to repair the real problem, a hair line crack on one of points against the plastic wall (its a row of 8 or 9 points) just look for crack on one of them, might need a magnifier glass. when you find it you will need to re-solder that point and any other with a crack in it. make sure you don't solder 2 points together.
then just put it back together and in the jeep and your good to go.