Seems pretty straightforward:
Code C0306: Transfer Case Motor
The transfer case motor is a bi-directional, permanent magnet, D.C. motor. When energized, through motor control A or motor control B, the ground iswww.autocodes.com
It's either the encoder motor or wiring.
I think "cleaning all the grounds" isn't enough... you might try getting a meter and do some electrical checks at the pins involved. IF the code description is correct, the problem isn't grounds, its powering that is getting shorted to ground or open.So I still haven't solved the issue for the code C0306. I changed the brand new encoder motor for a new encoder motor and still no luck. I also cleaned all the ground wires that I could find. Especially the one under the driver seat under the truck that is located on the cab mount. Still no luck. I called the chevy dealership and they said I would have to get the tccm flashed. What should I do?