Dash Security light

I have a 2000 s10 Blazer and it runs and starts fine. The Security light on the dash usually just comes on randomly when driving. When the key is put in all the lights come on as a test and after it starts the light goes off as normal. The Blazer has power locks but no remote locks or factory alarm. I thinking a short. I know nothing about this light or its meaning. Any help would be appriciated. If there is a possible part I might need to test please let me know.

We have a 2000 Blazer with the exact same problem. Hope to hear some answers!

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