No Throttle

[tbrown5079]

Got the truck painted and now doing final assembly. Going slow, only want to do this once! One issue I have had since the first fire up is no throttle. Nothing. It starts instantly but goes straight to default mode (fast idle). Thinking I may have a ground problem I checked the pinouts on the computer ( there are 8 between green and blue ) and all have ground, with key on and off ( can I be sure it's not a ground problem ? ). I get 7 volts at the throttle pedal and throttle plate ( I thought it should be 5 ) . All the components came from the same vehicle ( a 2007 GMC Sierra ) and Wait For Me performance did the harness. The check engine light comes on when you turn the key on and goes out when it starts. there are no codes in the computer ( just checking with a cheap scanner ). Where do I go from here? How can I check for a bad component to eliminate them one by one? Anyone?