I had this code P2002 and ETC light come on last Nov. Turned out to be a leak from one of the DPF differential pressure sensor steel pipes fitted to the DPF canister.
You could get under the Jeep and see if any soot is leaking from the pipe, it will be obvious as it blows all over the transmission.
Or of course i could be a leak in the pressure sensor rubber hoses.
https://www.google.co.uk/url?sa=t&rc...g0vyta13MbrlLw