..ok looking for some direction.....picked up a 2000 blazer 4x4 was told ecm was bad, after general tune up stuff having 192,000 miles (distributer,cap,rotor, plugs ,wires, new spider injector assy.) replaced ecm, runs mint. 4x4 doesn't engage- disconnected battery--heard clicking from TCCM first attempt, now no noises. Unplugged TCCM cleaned pins-and connector...not really corroded...no change....2HI dimly illuminated on buttons (3 button system) one plug from body control module was unplugged when i got vehicle......it had a remote starter installed...which i removed to eliminate from mix......could whatever killed ECM also have affected BCM or TCCM ? ? when new ECM installed does this affect other systems ? ? they not communicating ? ? just throwing it all out there.......any thoughts would be appreciated......not sure where to start now.........Thanks

 

try unplugging the TCCM if you havent already then plug it back in and try it.

Then with the engine off and key in run position press the 4HI button and see if you can hear the transfer case shift

 

.....yea i did the unplug and re-plug the tccm thing a couple times.....nothing no lights flashing...didn't hear encoder motor

 

did you check the fuse ?

 

Oh sorry i thought you said you just unplugged the ECM

 

yup fuse ok....tried the re-programming tricks i read about, like disconnecting battery for half hour...or unplugging TCCM for two min then turn key on and off five times.....been reading lots of posts on subject looking for hints