I have a 99 Blazer with the Auto Trac 236 transfer case.

I just installed a new (4) button controller switch in the dash this afternoon.

The AUTO 4WD button is staying lit up even in all the other modes (2HI, 4HI, 4LO).

What's keeping the AUTO 4WD button to stay lit up ??

 

Do you know that when you push the other selections its actually going into them,it may be staying in A4wd

 

I'm not sure what the heck it was doing.

I did install a new (used) Transfer Case Control Module that cured my Blazer's 4x4 woes!