Part time light stays on

Buddy brought over his 1999 WJ 4.0L np 242 auto and his Part time 4x4 light on the instrument panel does not go out when shifted back to 2WD. I gave her a run through and the 4x4 worked when shifted and it does disengage when shifted back to 2wd but the light stays on any thoughts would be appreciated thanks.

The switch on transfer box is. Same issue on my Girls 99 ZJ, I just disconnected it and light stays off.

Thank's I'll run that past him appreciate it.

yep, that is a switch problem. if he wants it to work he can replace it or give the "shot of wd40" a try first.