There is a procedure for doing a hard reset and a soft reset on the 8.4 radios. Perhaps someone can chime in as to how it is done....hopefully the procedure is the same on yours....maybe this guy @Ram4Sam
Mine froze today and I tried the hard reset like on my 13 and it didn't do anything. It was actually the first thing I thought of when the screen froze. I tried it in a few different ways and nothing reset it.
When I shut the truck off and restarted it the screen was fine.
2019 3500 SRW 4x4 CTD Aisin CC LB Limited Delmonico Red w/rear air
Previous rams 2000 2500 slt + qc lb 4x4 v-10, 03 qc lb 2500 4x4 hemi Laramie, 07 3500 qc lb 4x4 5.9 ctd Laramie. 2013 Ram 3500 Limited SRW CTD Aisin 4x4 CC LB. All have been black