I was in a GRF-3M on Alpine Peaks. I was on top of one of the mountains, and I jumped off. When I started using my jumpjets, I got a heat shutdown out of nowhere (I had not fired any weapons at that point and was at the baseline heat) that lasted about six seconds, and when I powered back up, my mech exploded. This was before any mechs from either team had engaged, and again, I had not fired any weapons or performed any other action that would generate heat, except for using my jumpjets and moving.