doing some research and the code 2 seems to point to an issue with the encoder motor. maybe not strong enough to fully engage the TC? or maybe the shifting is getting jammed up inside? but there are times when it will shift into 4x4 with no grinds. how hard is it to replace the encoder motor? what all is involved? i did find the motor on the side of the TC any help is appreciated

 

Never done one, I do not believe it's a major project, there might even be some youtubes on it. I have seen photos of the gear inside it broken. There is something in the back of my head about alignment of the gears that needs to be addressed properly. Make sure you get the procedure down correctly before any power is applied so as not to tear up the new gear.

 

i cannot find anything on youtube for a s10 encoder motor removal. anybody here?

 

Looks like you need to pop the front of the drive shaft, no biggy.

ZR2 encoder motor instal questions? - S-10 Forum

 

UPDATE: i got the encoder motor off, had to remove the driveshaft but could not pull it out. im not sure but it looks like a pin is missing in the last pic unless it is supposed to be like that. also it does not look too bad i dont know what to look for on it though. i tried to move the peg on the TC, the motor was still off i put a 9/16 wrench on it and tried to turn it counter clockwise and i could not move it or i didnt apply enough strength how hard are they to move?. can somebody chime in with some good news?

 

ok i got the transfer case to engage into 4hi (one click from 2wd) i put the truck in N. im using a 9/16 hand wrench. once i got in 4hi i noticed a little play in the shaft. is that normal? or is there too much slack and my real problem is in the transfer case itself?
2000 Chevy Blazer 4x4 233-C transfer case issue? - YouTube

 

ya poor bugger! most of this thread is all you! keep the information coming as you learn things though - I've got similar issues I've got to get worked out once I get the thing actually running.... (fuel pump enroute)

Checked your vid - play looks normal to me, about the same as on my other functional truck

7 pins is normal for the 233

the 'unreliable' changing modes/range is the same as what mine is doing and the previous owner has already changed the dash switch and module so I'll be going after the encoder motor next myself.

You've got the unit off the truck now - go get another from somewhere that doesn't hassle about returns (Canadian Tire around here) - if that's not the trouble take it back and go after the dash switch or TCCM

EDIT:
HEY! I just noticed the thread you got pointed to was to a ZR2 site! I assumed you were getting pointed at one of the articles on this forum. Lotsa good articles here: Tech Article (DIY) Index
That's the section warthog was talking about - I was looking at the 4x4 no worky and NV233 no mode switch threads myself - definitely worth the read

 

wow sooo much info to absorb in one time lol but thanks for it all it helped out man i never noticed the "4x4 no worky" im having a problem with my hvac it only blows out the front vents no matter what my selector is on maybe i have my problem in the vacuum system

on the other hand it might be a problem with the motor i was able to shift into 4x4 a couple times before the selector switch went blank during my final attempt. at that point i lost reverse and when i shifted to drive even while i was not moving i could hear grinding noise coming from under the truck . i cut the motor off there and thats when i took the motor off. i am able to shift it to 4x4 with my wrench and as you see from the video it does engage and disengage in the transfer case.

 

im gonna put the battery back on, start the truck, remove the battery, and try to engage 4hi with my wrench and see if the front actuator pulls the cable. if it does im assuming all the vacuum is working and my problem would be with the motor. ill also jack up the front and try to turn the front right tire to see if my axle engages any other suggestions?

 

UPDATE: i can verify now i have vacuum to the front actuator when i manually engaged the TC to 4hi i saw the diaphragm suck all the way in and i took it out and it released. i did not check the front axle engagement cause i have the front drive shaft off and was thinking it would probably spin anyway since it would not have connected to the engine. so i must have good vacuum am i correct? once i get the drive shaft back on i will check the front axle