RonBrackeen

i need the electrical diagrams for the 4wd for my silverado, any help is appreciated

tech2

which tcase do you have

RonBrackeen

I have the NVG 246 case

tech2

tech2

here is one of the two. don't have the switch schematic.
the tccm will store fault codes but they are accessed thru chassis not powertrain. What symptoms are you having?

RonBrackeen

I have changed switch lights upon startup, sometimes neutral, sometimes auto4wd, occasionally 4wd low. I also have had lights out on the switch. Usually when I have incorrect lights, I can put the truck in neutral and I can push the correct button and the truck will shift to that position.
Things I have done, cleaned all connectors I could find, cleaned the refurbished the grounds below the drivers door, replaced switch, replaced case motor two years ago, and replaced tccm just last week. The truck once started up in auto 4wd and the front diff was actually engaged and shouldn't have been. I don't give up easy, but I needed these prints so I can start doing some wiring checks for bad connections or broken wires inside the insulation. Thanks for your help, any of your knowledge would be appreciated. Ron

tech2

not clear on the symptoms. when you push the button to make a shift change...what happens with the led button indicators. does it flash on the mode button pressed and return to the mode that it was in....not completing the shift?

RonBrackeen

When I push the button to make a shift change, it completes the shift and the correct button indicates correctly. Sometimes when it starts up in 4wd low, it is only indicating 4wd low, and is actually still in 2wd. If i start rolling slowly, it will complete the shift to 4wd low, but will go to 4wd hi, and to 2wd when requested. Since the system actually works correctly when the different mode buttons are selected, it appears that it only malfunctions when the vehicle is started. This leads me to believe its a loss of signal, or connection issue. I may be on the wrong path, since I have not worked on or studied on this system before now.