99 Blazer LT 4x4 will not engage

You get one problem fixed..theres another... Have had this problem in the past and had the TCCM replaced. This is equipped with the 4 button switch, 2 hi, 4 auto, 4 hi, 4 lo. When you select any of the 4wd buttons, they will blink and not engage. At first I couldn't here the TCCM click but then pulled the fuse and had it relearn. Now it clicks but does not engage. please advise.

The auto transfer case needs to be put on a transfer case capable scanner and read out data and do shift test built into sanner and read and clear codes.
Post back any codes.

There are no codes. You can see it looks like the front axle wants to move when the car is in 4x4 blinking light mode after shifting through the gears at the same time(vehicle jacked up of course). But will not fully engage.

Ehh...It was a Vacuum leak! Actually a vacuum hose that came from the Solenoid at the wire wall running toward the underside of the Brake System but wasn't hooked to anything. I couldn't see where to hook it up so I plugged it for the time being, everything is shifting fine.

How did you check for codes?
With transfer case capable scanner?

Get a vacuum diagram and get the vacuum hooked up right.

When checking for front Axel lockup check with engine running and hold right front tire and spin when front drive shaft is turning the right front tire should rotate if locked in.

How did you check for codes?
With transfer case capable scanner?

Get a vacuum diagram and get the vacuum hooked up right.

When checking for front Axel lockup check with engine running and hold right front tire and spin when front drive shaft is turning the right front tire should rotate if locked in.

My neighbor has a Scanner, he checked them for me. Keep in mind I had the battery disconnected a few times last couple weeks working on ignition problem so all codes were probably wiped out?

Where can i find a Vacuum diagram?

Was it a transfer case/transmission capable scanner?

Factory repair manual or
http://www.alldata.com/products/diy/index.html
Most Public libraries have car repair info.
GM Dealer might copy it off for you.