Stuck in 4WD

[George B]

Was this on your '13?

No, I admit it was on my NBS but The control system works on the same principal. Also used the same process on our Envoy.

I went and read the troubleshooting that was shared. Thats not too hard to do.

 

[wsteele]

No, I admit it was on my NBS but The control system works on the same principal. Also used the same process on our Envoy.

I went and read the troubleshooting that was shared. Thats not too hard to do.

It seems on the later models the motor and position sensor is separated. It looks like there isn’t any need to set the transfer case in a synchronized position between the motor and the TC, as the position sensor is not part of that pair. The TCCM knows what position the TC is in and only needs to tell the motor how far right or left it needs to go to select the commanded position.

On my 2007, it is the same as your NBS with the motor and TC keyed to each other. It is interesting to dig into the subtle changes in model years. In my '07, I have the NP8 TC/motor (old style, which implies the push button style TC drivers control), but I have the modern NQH style rotary switch. I guess they handle the differences in the TCCM calibrations.

I am still stumped what the motor learn does.

 

[George B]

It seems on the later models the motor and position sensor is separated. It looks like there isn’t any need to set the transfer case in a synchronized position between the motor and the TC, as the position sensor is not part of that pair. The TCCM knows what position the TC is in and only needs to tell the motor how far right or left it needs to go to select the commanded position.

On my 2007, it is the same as your NBS with the motor and TC keyed to each other. It is interesting to dig into the subtle changes in model years. In my '07, I have the NP8 TC/motor (old style, which implies the push button style TC drivers control), but I have the modern NQH style rotary switch. I guess they handle the differences in the TCCM calibrations.

I am still stumped what the motor learn does.

Thats good info. Thanks for sharing it. I may be just muddying the water here. Goi g to sit back and see what how this plays out.

 

[wsteele]

Thats good info. Thanks for sharing it. I may be just muddying the water here. Goi g to sit back and see what how this plays out.

Ha, you can't be muddying it any more than I already did, tracking on the old style TC motor install. It looks like the new style is a 10 minute job. Pop the old one out and install the new one. Done. I think... except for that pesky motor learn...

 

[Fless]

Ha, you can't be muddying it any more than I already did, tracking on the old style TC motor install. It looks like the new style is a 10 minute job. Pop the old one out and install the new one. Done. I think...

That's why you got the old style one.... so it would be a challenge.

And, yeah, we sure provided a lot of info that doesn't necessarily apply!

 

[wsteele]

That's why you got the old style one.... so it would be a challenge.

And, yeah, we sure provided a lot of info that doesn't necessarily apply!

Well, selfishly, it applies to me, which is largely why I am spending the time. I want to keep that beast a while. The more I know now, the less aggravation when something breaks, and I know it will.

 

[easymoney]

This is a shot in the dark but my 04 has had a lot of these issues did you try the start in reverse to reset all the controlers? On a 2004 turn the key to on but dont start it. Put it into reverse then try to start it in reverse. It obviouly wont start in reverse but it resets all the controlers. I had to do this to reset the speedometer and air conditioning actuators. It should reset the 4x4 controller…

 

[dnt1010]

 

[UpAndDown]

Just wanted to update this thread. Finally got around to working on the truck yesterday. It was the control module. I replaced it with the Dorman unit that has a programming procedure and it works again. Thanks again for all of the help. This is a great site.

 

[Michaelt]

It is likely the transfer case actuator (tc motor) or the transfer case control module. Both require some work with the Tech 2 or other high end scan tool (like a Snap On) to complete the repair.

If you are near anyone listed in the Tech 2 owners sticky above, maybe reach out and see if they may be able to help with that side of things, then just do the diagnostics listed in @swathdiver’s post above.

if you still don’t know what to do, take it to a dealer, it will be a fairly expensive repair, like $500-$1200, depending on if it is the motor or the tccm.

Just got a dealer quote of $660 to replace the actuator motor. Just hoping that's not a 'guess'.