Tranny shift issues

[Avalanche05]

I've got a 2002 Chevy Silverado with codes p0740 p0785, p1860 they was another code before I cleared it and started checking. I have power through the ignition and power at fuse Ing 0. Even have power at the plug on the transmission. Please help

 

[Mooseman]

Although from the GMT360 Drivetrain FAQ, it's the same transmission so these should point you in the right direction.
Transmission with multiple codes
Another Transmission with Multiple codes
More Multiple Codes