Yes that could be done, but as I mentioned at the end of my last post, there is audio and the sequential LED start up and shut down to take into consideration.
At this point I have solved my problem with a simple 555 timer circuit (pretty much what I was going to use from the beginning, but I thought I would check on my thinking
).
I just finished testing it and it works perfectly. The 555 timer emulates a sensor "firing" every 90 seconds, thereby keeping the auto shutdown from occurring.
Thanks to all that responded!!