Hey all,

I am having some problems with my truck that I'm hoping some of you have encountered in the past.

2007 Chevy Silverado, Crew Cab, 4wd, LTZ, VortecMax (6.0)

I recently finished putting together the last few pieces of my long travel setup, and upon completion of installing some custom length front axles, discovered the issues with the 4wd system.

I am unable to shift the transfer case out of Auto. Currently stuck in the auto mode, with a single LED below indicating that I am in auto. I have replaced the 4wd selector dial to rule that out as the problem since it seems to be common, more so on the older push button 4wd systems but common none-the-less.

I pulled a C0306 code, which by definition is "an open, short to voltage or short to ground in the motor control A or motor control B circuits or an open or short to ground inside the motor."

I tried replacing the Transfer Case Encoder Motor, as well as the TCCM with no luck. Nothing changed, leading me to believe it may be wiring? I am unable to track down the wiring schematics of the connectors; if anyone has this that may help.

Occasionally I try pulling the TREC fuse under the hood, which to my knowledge is the only 4wd fuse on the truck. When I do this, every once in awhile I can turn the dial to 2wd, and the led indicator below "2wd" will flash as if it's trying to make the switch, but then returns to the single LED lit below "Auto" as if it encountered a problem when trying to change gears and stopped. This rarely happens, but I have seen it and am not able to reproduce this consistently.

Currently, as soon as I turn the key on, I can hear the front diff actuator, and it locks the front axles. I have pulled the harness from the motor so I can drive it without it being completely locked up front.

Anyone have any experience with this problem?

 

Update:

Disconnected negative battery cable and let it sit for awhile. Was able to then get into 2wd after reconnecting. Drove a little ways and was able to switch to 4 hi and back to 2wd.

Drove home and encountered a service 4wd message with the same C0306 code. Still in 2wd at this time as I am afraid to test it and get stuck in 4wd again

 

Anyone have any ideas?

 

Id check to see if theres any corrosion in the x109 connector....