Does anyone else remember the old show on the USA Network called "Up All Night" hosted by Gilbert Godfrey? Well I originally caught this super cheesy B flick back then. Filmed in 1986 a bunch of teens hide inside a furniture store inside a local mall to throw a big party after hours. What they don't know is the mall is guarded by 3 robots and that the mall is sealed off from the outside world come 12 midnight. A bolt of lightning proceeds to strike the mall which in turns short circuits the robots and turns them into killer robots! Told you it was cheesy. By the way, this movie is sometime referred to simply as Killbots.
I'm only including this movie to the feature because of how terrible it is - not because it's a good movie. It's watchable, but I can't really recommend it. You can probably find most of the good scenes on YouTube (like the one below) if you search for them. It'll save you a lot of time.