With a little research, according to FCA this code should be allied with the Coolant valve sticking in open position in relation to either a 5.7L gas engine or the 8HP70 transmission. Since this is in relation to a ED I would go first to the Transmission TCM, that big finned box on the transmission with coolant lines and ATF lines, and perform diagnostic procedures related to that TCM. It also comes up as a false code due to incomplete flash ECM programing, so it could be a false call. This would be the system which maintains the "proper" temperature of the Transmission by switching from Engine Coolant heating to Cooling once up to operating temperature. So basically it boils down to a Dealer Tech with enough knowledge to figure out which situation you have. Good Luck. I finally found a dealer that I trust, can verify the information I already know, and this dealer has made a world of difference in Warranty issue resolution for me.
