I have a 1999 blazer LS. I attempt to put it in 4wd and i hear the clunk in the rear but the 4lo or 4hi (whichever im trying) light just flashes. Then when i put it back in 2hi, i hear the clunk and a click in the tccm, which i dont hear when i try putting it in 4wd. I took off the tccm and checked for corrosion and there was none. My "service 4wd" light is on. Sorry im posting like this, im new to this site and cant figure how to make a new post.

 

*Moved to a new thread instead of part of another thread discussing a different transfer case* - Please use the new thread () button located at the top of each forum section where posting is allowed if a search for a fix has not presented the necessary information to diagnose & fix your problem.

You pretty much need to get the TCCM scanned to pull the codes. The codes will point you in the right direction.

 

thank you, ill gave it a shot