There are Connect IQ apps that will show the battery status.
Do you know one specifically? I tried one but could not get it to work.
Connect IQ data fields do not show on the Varia Vision
Just to clarify, you want the battery level to show on a model 1000 and not the Vision device? The tail light is not related to the Vision device.
The best Connect IQ app I have seen is called "Tail light field". Allows tail light to be turned off with radar still on. You won't have to go to the light widget anymore which takes more screen presses.