DEF re-gen cycle frequency

as stated in another post the DEF system does not regen but the diesel particulate filter (DPF) does. if the regen occurs when driving there is no effect on the engine operation and no indicator light unless the vehicles speed drops below about 7 mph during the regen then a high exhaust temp light will come on until the DPF and SCR catalyst cools down or the vehicle speed goes back up, if the high exhaust temp light is on it is a good idea to not shut the engine off until the light goes out. I am assuming it is probably a ISL cummins if it is next time you are in a cummins shop and they are plugged into the ECM ask them to print out the regen history, it might surprise you how often I happens.