EL Panel removal?

[mshac]

Hope you don't mind me jumping in here on your thread.

My EL panel lights sometimes go off and on randomly. I noticed an entry in the airframe log a few years back that mentioned "Repaired panel backlight ground connection."

Questions:
1. Where is the EL panel lighting ground connection?
2. Could the rheostat cause the lights to go off and on?

Thanks in advance if anyone can enlighten me.