Alright, checked the voltage at the encoder and all were 4.95 Volts which is obviously close to the 5 that is needed. Changed the encoder with one from a scrap yard, that didn't work either.

Now when I reset the TCCM and press the 4HI switch the light will blink and TCCM makes several clicks then the truck kicks back into 2HI. After pressing the switch a few more times it will stop blinking altogether and I only get one click from the TCCM.

Is it possible for the TCCM to be bad and still be "clicking"?

 

Have you read through this thread:
NV233 transfer case / encoding motor switch

The 1st Gen NV233 codes are the same as the 2nd Gen NV233 codes so this the link below will give you a run down of each code:
OBD2 Non-Automatic Transfer Case Diagnostics

 

Your welcome, glad it worked for u. Your right, anyboby that ownes a blazer with a push button 4wheel drive should write this down somewhere...lol. All the people i have told since i picked it up, which has been 8 now 9 so far it has fix 7 of them and most not all has accidently hit the 4Lo button while in park or in drive...so this may just be a flaw in the module program or maybe just old age and heat over the years, something causes it to lock up or freeze up.

@Longer02....the TCCM is the smaller module piggyback on the ECM, just checking to make sure your unplugging the TCCM and not the ECM?...im just double checking with ya...cause from the sounds urs is making, sounds similar to what mine was doing....

 

I have searched and read every thread on the internet about this problem. I checked voltage at the encoder motor, I replaced the encoder, I have checked for vacuum leaks and everything. It has to be something with the encoder (could have gotten a bad one) or the TCCM. I am thinking TCCM however. Like I mentioned once I reset the TCCM and hit the switch the 4HI light will blink a few times, the TCCM makes a few clicks, then the light goes out. I get not action from the encoder at all. Once I try to shift it a few times then all the TCCM does is click and I get a very brief light at the 4hi switch.

I have ran the codes and get a code 1 and 3. I read a thread that says 3 usually means the encoder but I tried that. Maybe I need to break down and buy a new one? Or does 3 mean the TCCM needs replaced?

Can the TCCM be bad if it is still clicking though? I thought the junkyard close to me had one but evidently they can not find it now. I don't want to order something online and not have it work either.

I am at a loss here. I have tried everything short of buying a new TCCM or switch, however it appears that switch is getting power. What should the next step be? Thanks.

 

Up top. Does anyone have any insight to my post above? Thanks for all the help.

 

where do i need to unplug it from?
do i need to unplug the encoder motor also ?

 

Just unplug the plug that's on the encoder motor itself, witch is directly on the transfer case, it has a 10mm bolt holding it on. just unplug it, wait a few mins.. the plug back in and tighten up the bolt again. after that pull out the TCCM "fuse" for about 20 mins then put it back, cycle the ignition switch 5 times (to the run position and back) make sure the 2 lights on the Dash's control switch light up all 5 times before you put it back to the home position. After that start it up and hopefully everything is back to normal.

 

When I unplug the TCCM should the truck be running or be off? Will the TCCM be obvious to me?

 

Your not unplugging the TCCM itself, your just supposed to unplug the TCCM "FUSE". Its under the steering column in the fuse box, not too hard to find. Also I recommend you leave the truck turned off while the fuse is pulled out.

 

alright thanks. someone showed me this thread, becuase I was having my own 4x4 problems, where my dash switch wasnt doing anything. So I'm hoping by unplugging it will help me get my 4x4 working again.