red light next to engine temp

[AMcCormick]

what is the little red light that is just to the upper left of the engine temp gauge? I have only seen this come on at start up when everything lights up.

 

[PBJ2500CTD]

I beleive this is the Security system light...

14. Security​

The light will flash rapidly for approximately 16 seconds
when the vehicle theft alarm is arming. The light will
flash at a slower rate after the alarm is set. The security
light will also come on for about two seconds when the​

ignition is first turned ON.