1 - There should be an inline fuse where the electrical wiring connects to your truck.....
2 - you should be able to pull off the vacuum line that runs to your cylinder and put your finger over the line and feel a vacuum there when the e'brake is on and the truck is at idle..... if there is no vacuum you need to make the following tests... .
3 - at the control solenoid test to see that there is power to the solenoid and that it is grounded..... if there's power there and the ground is good and no vacuum passes the solenoid than the solenoid is bad..... if there is no power to the solenoid you need to solve that problem... .
4 - you need to have 22-25" of vacuum for the cylinder to pull the valve..... if you have that much vacuum the cylinder is bad or the valve is stuck... . if you don't have that much vacuum at the cylinder either there is a leak, the solenoid is bad, or the vacuum sourse is bad.....
Each of these steps has several additional tests to run down the problem... . if you make these checks and still have problems get back to us...
Jim