On my truck it ranges from 0 to about 85 at full throttle. Just turn the key to run, but don't start the vehicle. You may have to press home then gauge to make the display activate when the engine is not running. Press one of the gauge buttons until TPS pops up. Then slowly push the pedal to the floor and release it. The numbers should go smoothly up to the max, and back down. If not then you probably have a bad TPS.
Yea, I have noticed that GM vehicles read 0 at idle. My car reads 9 at idle which I thought might be a problem, but now that I hear that the Element is the same that must just be a Honda thing. I will try that little experiment with the TPS later today (I always feel weird saying that when I get off work at like 1 in the morning. It still feels like it's the day before!).