4 Wheel Drive/SUVs: 1996 suburban wont go into 4x4, driven unit, test light

Question
My '96 Suburban 1500 4x4 won't shift into 4 wheel drive. When I push the button for 4 Hi the light just flashes and stays in 2 wheel drive.  Fuses are good.  Help please.....

Answer
Alex,

This could be anything from a bad switch, broken wire or a a bad ground.  I would purchase a repair manual and a test light or multimeter and start chasing out wires looking for an open circuit.
These manuals cost around $20 and are great for trouble shooting.
This could, also be a failure in the transfer case itself, or the front differential may not be locking in.  Many of these models have a motor driven unit that locks and unlocks the front differential.  If these go bad, then the front end will not engage.

Carl