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Posted

Thanks for all of the replys.

 

Darin - I am dealing with a different dealer today than I was yesterday. The one yesterday was close to my office - this one is close to my house. I have a feeling that the dealer yesterday was seeing several codes related to this problem and that they thought the encoder motor was causing all of them. I don't think I wasted my time or money changing it out last night - I just think it was one of many problems.

 

I wish I felt more comfortable with all of the electrical stuff. I just hope that at the end of the day - although I will have $1,000 less in the bank - it will be fixed.

 

I now appreciate the simplicity of a floor-mounted transfer case shifter. I don't think you can get those anymore, can you? Probably on a work truck.

Posted

Wow. I know your pain all too well. I went through all that a few months back and still don't have the problem completely corrected. I though have the lock circuit low code, changed the encoder motor, the push buttons and the tccm, I did buy the 60 buck one from a salvage yard and slipped it in myself and still NO luck. I Gave up I can pull my ATC fuse and unlock the front end but the transfer case will not shift to 2hi or 4lo just 4hi and auto. If I need 4hi I just put my fuse back in. I know its not good but i didn't know what else to do. Please post your outcome, I am curiouse to know how you end up. I think I might need the dealer to program the tccm and the new Encoder motor. I ohnestly exhausted myself with the whole deal and simply let it be.

Posted

Gunner, I can imagine you are exausted with the problem - I was after only two days of dealing with it. The final outcome is that the problem is fixed after they replaced the TCCM. I have a feeling that they had to do some work with a programmer getting everything to sync back up - so you might try going to a dealer or transmission shop (that has a scanner that can read and program the transmission codes).

 

The end result for me was a new dashboard switch, new encoder motor, and finally a new TCCM. The switch was me trying to fix the problem - the original switch was probably fine. There was a code thrown for the encoder motor so I replaced that...didn't fix the general "stuck in 4WD" problem - so off to the dealer and there was a different code that said the TCCM needed to be replaced.

 

Anyways...thanks for all of the advice. Hopefully someone reading this post in the future that is having a similiar problem will find it helpful.

Posted

Nathan, congrats on finally getting it fixed. On the bright side you shouldn't have any electrical issues with the 4WD system for quite awhile now. Thanks for keeping us posted. :thumbs:

  • 2 years later...
Posted

Thanks to everyone who commented on this thread. My 2004 Chevrolet 1500 Z71 recently had an encoder problem. Sometimes when I would crank it it would be in 4L or the Neural light would be on letting me know there was a transfer case code. It would always shift back to 2WD with no issues. The problem seemed to get worse anytime the truck was driven over 2 hours straight.

I used this thread to change the encoder motor. It was very easy. It took under an hour and went smoothly. I did need to rotate the transfer case encoder motor shaft a small amount to get the new encoder to line up. I just used a crescent and rag. Otherwise no issues, thanks to your thread. Dealership $800.....do yourself......1 hour.....$260 part.

  • 3 years later...
Posted

I am doing the transfer case encoder motor fix on my 2002 chevy silverado. The obstacle I've ran into is, after I got the encoder motor off I decided to cycle through the 4 different transfer case positions, I can get 4-Low, Neutral, and 4-Hi but I can't get it into 2-Hi manually with a crescent wrench. Is it possible the transfer case has seized up? I did a transfer case fluid change and it improved the manual shifting between the 3 available positions but I still can't get the 4th position. Has anyone else had this problem? Any suggestions?

Posted

Tires off the ground and transmission in neutral ?

 

If that shaft falls inside you are screwed , ask me how I know

Posted

I haven't had the tires off the ground when manually cycling through the positions. I've been able to shift to the other 3 positions with the tires on the ground, the transmission in neutral and the parking brake on. Next time I'm working on it I'll jack it up and see if that solves the problem.

 

Ouch.....I can't imagine how the shaft could fall inside, but I'll keep that in mind when manually cycling.

Posted

I haven't had the tires off the ground when manually cycling through the positions. I've been able to shift to the other 3 positions with the tires on the ground, the transmission in neutral and the parking brake on. Next time I'm working on it I'll jack it up and see if that solves the problem.

 

Ouch.....I can't imagine how the shaft could fall inside, but I'll keep that in mind when manually cycling.

Iirc I removed the detent for some reason , and in it went , then the tcase came out and apart lol

  • 5 months later...
Posted

I had all 4 tires off the ground and the transmission in neutral. And while manually shifting I could only get 4-Hi, Neutral and 4-Lo. It definitely felt like there was one more position from 4-Hi going the opposite direction of the Neutral position, but i couldn't get it to click in to place, even with a cheater bar on a stubby wrench.

 

I read another post, where people have been able to get a troublesome transfer case to shift to 2-Hi by driving in reverse and then selecting 2-Hi, I'm thinking if I put the encoder motor back on and try shifting while driving in reverse, that will be my last possibility before declaring the transfer case shot (even though the encoder motor was diagnosed as the bad part by a transmission shop). Thoughts?

 

Thanks,

 

Joe

 

 

the history for this issue is:

I am doing the transfer case encoder motor fix on my 2002 chevy silverado. The obstacle I've ran into is, after I got the encoder motor off I decided to cycle through the 4 different transfer case positions, I can get 4-Low, Neutral, and 4-Hi but I can't get it into 2-Hi manually with a crescent wrench. Is it possible the transfer case has seized up? I did a transfer case fluid change and it improved the manual shifting between the 3 available positions but I still can't get the 4th position. Has anyone else had this problem? Any suggestion?

  • 7 months later...
  • 4 years later...
Posted

I have a 2015 GMC Sierra with the electronic 4WD...its currently stuck in 4WD-High... I cant seem to get it to shift into anything...Do I need to have the codes cleared first?  How do I tell if its just an actuator? Thanks in advance....

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