My check engine light came on, it was diagnosed as error ...

Hello and thank you for using JustAnswer. My name is \*\*\*\*\* \*\*\*\*\* I will do my best to assist you. During this conversation you will be given an automated offer for a phone call. You may accept or decline that offer.I don’t personally offer this service so if you take this another tech may call I’m sorry that you’re having trouble with your vehicle. I will do my best to help you resolve them. Please understand that I do not know your knowledge or capabilities so I may need to ask questions to find out basic information to help solve your specific problem. My aim is to give you the best service possible and to help you. If you have any questions or concerns, please don’t hesitate to let me know. Sometimes it may take a moment for me to respond because I may have to look up information about your concern. I appreciate your patience and will provide responses as soon as possible. So this is a common code for the 3.6 Wrangler and the thermostat always fixes it. Make sure when doing it to bleed the system with the bleeder screw on the t-stat housing and be careful tightening it up cause it can break easily as it is plastic. Take the screw out and fill the system until it runs out the hole the install the screw. The job is really easy and can be done in 15 min or so.

I just need to replace my thermostat? Do I need to flush the coolant too?Or is that what you mean by "bleed the system"?

Yes change the t-stat and flush the coolant if it is the factory coolant in it. It is good for 5 yrs so it is due if so. When i say bleed it that means get all the air out of the system. An air bubble in the system can cause it to overheat and have no heat in the cabin. Anytime the engine sets lower than the radiator you have to bleed it. These Jeeps have to be bled. The screw on the t-stat housing will do this for you. It is simple just follow what I said before.

ok, thank you so much!

No problem! Glad to help.