4 Wheel Lock Light on dash ?

[78k10cd]

I was installing a radio in my truck and looking for an ignition wire and found a yellow one and tested it against a hot wire and it lit up the 4 wheel lock light on my dash! i didn't even know there was one!

Can anyone tell me where that wire goes to? fuseblock? wire from transfer case?

While I'm at it, any tips on the best wire to use for the radio's ignition wire? thanks in advance!

[Snuke87chevy]

My cd player is wired constant hot. Try looking in a mnaual to see where a radio would run itn othe fusebox at.  I'm not sure where that 4x4 light runs to but it does eventually lead to the t-case.  It's a black plug with two wires coming out, can't remember what side its on though.