Updated 10/13/2019 - After 260 miles the display started again going on and off on rough roads. I added a plastic shim (a plastic toothpick from my Swedish Survival Knife) between the side of the holder and the display. Problem solved again...for now. I've been sending ICE updates on this little problem to get their input.
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Note; The ICE Sprint FS E8000 uses the Shimano E6100 display with the E8000 motor.
While riding the other day the display would turn off and then right back on. I contacted ICE and they told me to check the display by wobbling it in the cradle as shown in the ICE video below. I was ready to turn a minor problem into a big production by checking all the wiring for a loose connection. A bit embarrassing that I didn't think about checking the display connections. Oh well...I'll still admit by lack of clear thinking and pass on what I learned to other Shimano Steps users.
Video from ICE Customer Service
If the above video looks like a problem you're having then the fix may be easy. On the back of the cradle is a screw that's used for security. If tighten enough the display will not come off the cradle. It also seems to make the display more snug in the cradle and keeping it in contact with the contact points.
I'll note here that my display problem looked like the one in the video but it didn't turn on and off while testing it in the comfort of my garage. My problem occurred while riding in 95 degree heat and generally when hitting a rough patch on the road. By tightening the cradle screw the display problem hasn't reoccured. Hopefully it stays that way. 70 miles with the adjustment and all is well.
Back of the E6100 display used with the E8000 motor.
If the display does loose contact with the cradle for a brief moment chances are contact will immediately be reestablished but you'll be without assist for a couple of seconds and you'll have to reset the assist level on the display. Luckily for me the battery stayed on and I didn't have to reboot the assist by stepping off the pedals to allow the torque sensor to set. Also the electronic Di2 shifter on my trike kept working while the display booted back up.
