2006 Silverado 1500 cruise control not working

[GMark]

I have a 2006 Silverado 1500 LS Crew Cab 5.3L and the cruise control is no longer working. No matter what I do the system will not set a speed and enter cruise control mode. I have done the following troubleshooting with multimeter and 12v signal tester:

 

• I verified the fuses are good
• I checked the operation of the multifunction switch on the steering wheel and it is operating correctly
• I tested the brake switch and it is operating correctly
• I tested the signals at the throttle actuator control / cruise control module 16 pin connector:
  • Cruise On/Off gry wire is 12v with cruise control on, goes to 0v when I turn off cruise control. I also verified this is controlled by the cruise fuse as expected
  • Brake Cutout lt blu wire is 0v, goes to 12v when I step on brake
  • Cruise Set dk blu wire is 0v, goes to 12v when the cruise set button is pressed
  • Resume gry blk wire is 0v, goes to 12v when resume switch position is selected

 

What else am I missing? Can the controller itself be bad?

 

[txab]

Check for stored codes with a reader. Some codes will not allow the cruise to activate

[GMark]

I should have included that in the initial post. My code reader comes up with no active, stored or pending codes.