ok I will try that, if it's turned off will the battery symbol still show in the 4th line?
Yes the battery symbol will still be there but it will not be red, or whatever color your switch is.
You could also load one of my fonts to test the switch. I made a Bluntman and Chronic diamond save. That font uses the illuminated switch heavily. It is a pfnt file, so all you need to do is download that one file and then load it to your saber. Turn on your saber in that font and the switch should definitely light up. If you use that font of mine and your switch doesn't light up then it is definitely a broken switch.
My Darth Vader font also uses the illuminated switch a lot. If you hate Jay and Silent Bob...
https://drive.google.com/folderview?id=1ITyyh5wwsWASi0IvNjJsRiVdEDT_2hC4