CHEVROLET BLAZER TRANSFER CASE ENGAGE

Yes I Was Wondering What I Need To Do To Get My Four Wheel Drive Switch To Work When I Try To Lock It In 4hi It Tries To But It Goes Right...

When I Push Any Of The 3 4 Wheel Drive Buttons The Light Blinks For A While And Then Switches Back Into 2wd.

When I Switch From 2h To 4hi The Switch Does Not Flash. Is This Normal? Also As I Read The Manual To Do This, It States That In Neutral...

This Is My Elderly Parents Vehicle. Four Wheel Drive Has Not Worked In A Long Time. They Are Away On A Trip And Left It With Me To Do Brakes...