Chopping Mall Bloopers & Goofs

AKA: Killbots
Chopping Mall Picture
Fighting back...
See the goofs, blunders and plain ole mistakes in the 1986 Horror / Occult movie starring Kelli Maroney, Tony O'Dell, Russell Todd et al.
Contributed by: Thomas DiGregorio
Here is a goof that may not be recognized immediately. In the scene with Dick Miller and protector 1, if you notice on the upper right of the mall in the background there is a light shining. Just as the robot electrocutes dick the light goes dark and this is shown just before the janitor gets zapped. What is going on here? Please explain!
Chopping Mall