iam having problems with my trans. it is giving me the codes of p0740 p0785 p1860 can any one tell me what they are and how to fix them

740 = TCC solenoid or circuit problem.
785 = 3-2 shift solenoid or circuit problem.
1860 = TCC PWM solenoid or circuit problem.
First check the fuse and then the wiring to them.
Here is a PDF link for the test on code 785.
http://members.troublecodes.net/crunch/Blazer.pdf
Go threw it and see what shows up and post back results.
Also welcome to AF on your first post.
MT