What is this little red light for?

[mandospd]

Hey everybody..just bought a 2000 extended cab XLT 4x4 4.0 litre V-6 with automatic...have already fixed the infamous drive line clunk...now I'm wondering what is this little red light directly below the fuel gauge..it's not in the intrument cluster behind the glass but in the black trim that is part of the instrument cluster..I removed the neg cable to reset OBD and when I got in my truck this light was on..goes off when you start up and drive but comes on when you turn off the ignition...the owners manual doesn't even mention it. This is not inside the instrument panel, it does not have an icon ,it is just a small red light, I am not asking someone to interpret the instrument cluster for me... I have an owners manual...what I am asking is that if someone out there knows what this light is for please respond....no guessers please

 

[Hazmat Ranger]

It sounds like it is an alarm system indicator. Normally when they stay on it is indicating the system is in valet mode. I have an aftermarket system, VIPER, and it will come on in valet, off when driving and flash when alarm is set.
Could be previous owner added the light for that purpose. Sorry if that seemed like a guess, but that is what mine does, just in a different location.

 

[Jspafford]

Don't cross post.