4x4 no worky
3 button 4x4 1997 jimmy
I tried this and i cant seem to get the lights to tell me anything (nothing-no lights blink).

Lights work on (4 hi) and (4 low) when i press them(does nothing when i press but clicks in dash ).

Also ( 2hi) light never comes on (idk why) .

Im pretty sure this is an electrical problem more than the hard wear
because i inspected the hard ware and it looks fine.

thats where i pluged in my code reader lol?

 

I have looked thought all the threads and i checked all parts of the 4x4 all ok ie: the vacuum lines, the acumilator cable and unit

I got my wife to sit in truck and press 4hi while i was under there:
I hear the encoder motor trying to engage it but no go , if i grab the shaft while its trying to engage it locks while im trying to turn it but when it done trying to engage the shaft turns freely again
i think the encoder moter is gone but im not sure , what can i do next im lost

 

Sounds like you have an encoder fault. There are posts that explain what each mode should result in as far as an encoder output. If you really wanted to diagnose the problem, you could back probe the encoder outputs and watch them as the TCCM tries to shift the transfer case. If they do not come out right, you know the encoder is at fault. But from the sounds of it, the encoder motor isn't fully engaging the transfer case and fails the shift.

The fact that your 2HI light never comes on makes me wonder if the switch and/or TCCM are functioning properly as well.

Suffice to say that you have not checked *all* of the parts and found them to be ok. Otherwise, your truck would have 4wd.

 

I have a '96, which also has the 3-button system. 2Hi has never lit up since I've had it, and I thought that's the way it's supposed to be, since that's the default setting. Am I wrong about this?

 

The wiring diagram from this thread shows an LED for 2HI...

 

Kyle, the transfer case is likely the same, but the dash switches are different. My Blazer's 4x4 lights are amber, not green like error_401's -- and my switches are in the center of the dash, above the radio. He described his as being on the left side, above the headlight switch.

Not that I'm trying to be picky or anything, but is it possible that the wiring diagram is for the Gen I 4x4 switch and not the '95-97?

 

The wiring diagrams I posted were from a 2nd gen.

 

check the harness behind the 4x4 module in the dash. mine never light up until i hit the dash. just pop the top of the dash out, then pop the 4x4 module out of the trim and wiggle the connector in the back, the light should come on for 2x4. if not, you have bigger problems as stated above.

 

not sure if this helps but my 4x4 wouldnt shift at all when I bought it, but turned out that the switch itself was all gummed up, the whole assembly just pops right off and I cleaned all the gummy stuff out and then it worked fine. Just a though since you checked everything else.

 

Silver, I haven't tried your suggestion yet -- but I'm probably not going to anyway, since I'm selling the truck.

But I bet it's a simpler answer even than that. Since it's in 2WD probably 99% of the time it's being driven, the LED probably just blew out. Honestly, I don't even care enough to fix something that small. But thanks to everyone for your suggestions.