4x4 inop 2000 blazer 4 button switch

hi i have a 2000 blazer and 4x4 is inop- no lights on switch and nothing happens-i have checked fuses and changed switch still nothing-i have read alot of these forums and wondering if its the tccm. i was told that if their"s a code for 4x4 it needs to be cleared? we tried unhooking the battery for 30 min and nothing changed. i'm wondering if the code needs to be cleared first,service 4x4 light is on.. if you have any ideas let me know i don't want to just throw parts at it. thanx tomcat:shakehead

i'm wondering if the code needs to be cleared first,service 4x4 light is on.. if you have any ideas let me know i don't want to just throw parts at it. thanx tomcat:shakehead

Get the truck scanned and see what diagnostic code you are getting and go from there. It will give you a better idea where to start.

we had it scanned by a gm tech and he said its the tccm, of course the cheapest new is 330.00 from gm parts on internet. we got one from a junkyard and put it in and when cycling key we here it clicking and the service 4x4 light went off after installing tccm. i was told that if tccm is bad and especially if the 4x4 was inop for a while the encoder motor will have to be changed also. we have made some progress but 4x4 still doesn't work, i'm thinking that the encoder motor is gonna have to be changed too. i'm up for ideas and i will get this fixed without going to a dealer and spending money i don't have,,thanx tomcat

What transfer case?

If the lights on switch do not light up it sounds like a power feed or fuse.
Check all fuses in all fuses boxes.

Does any light come on for a bulb check when key is first turned on?

you might want to try this first,the tccm is located on the pass side floor near the behind the bezel molding,below and to the right of the glove box.remove the panel and disconnect the tccm connector and check for corrosion.very common on this year.also you can flash codes throught the 4wd switch.here's how
<LI type=1>Turn OFF the ignition for 10 seconds. <LI type=1>Connect PIN 13 on the data link cable (DLC) to a ground. The DLC is located in the cab under the instrument panel on the driver's side. <LI type=1>Turn ON the ignition, with the engine OFF.
Observe the transfer case shift control switch select buttons for flashing codes. you can try this first.