[gherbert]

Shifting Into N (Neutral)
To shift:
1. Park the vehicle on a level
surface.
2. Set the parking brake and press
and hold the brake pedal. See
Parking Brake on page 9-41.
3. Start the vehicle or turn the
ignition to ON/RUN.
4. Shift the transmission to
N (Neutral).
5. Shift the transfer case to 2

.
6. Turn the transfer case knob
clockwise to N (Neutral) until it
stops and hold it there until the
N (Neutral) light starts blinking.
This will take at least
10 seconds. Then slowly release
the dial to the 4

position. The
N (Neutral) light will come on
when the transfer case shift to
N (Neutral) is complete.

Page 9-39 in the 2015 GMC Canyon Owners Manual

https://www.gmc.com/bypass/pcf/gma-.../2000/MA2827/en_US/6.0/2k15canyon3rdPrint.pdf

 

[gherbert]

Thanks for the quick reply! Unfortunately, I already tried this and it didn't work. I also tried running the relearn procedure from SPS and that didn't work either. I wanted to try manually turning the gear to the N position, I just can't find any indicator of the N position on either the motor or the gear in the transfer case.

You did with the parking brake on?

 

[gherbert]

Have you ever changed the fluid in the transfer case?
Does it go into 4HI and/or 4LO?

 

[gherbert]

No, I haven't ever changed the fluid. And no it won't go into 4H or 4L - stuck in 2H and giving me "Service 4x4" error. I tried reprogramming the TCCM and running a relearn from SPS, but I'm still getting code "C038D: Range Actuator Position Not Learned".

Well if you don't have enough fluid in the transfer case it will not be able to change.
One of your posts mentioned you had a 2015 Canyon. That fluid is 7 to 8 years old.
Could be a big part of the issue