Thumb Throttle wiring

We are wanting to use a thumb throttle as speed control for our Shell eco marathon hub motor vehicle. I received a thumb throttle from Bend Electric to use with our Eezee controller for our 350 W motor. I see there is a red, black and white wire coming from the throttle. We tried to test by putting red to 5V, Black to ground and then monitor with a DVM the white wire for 1-4 volt expected swing while operating the throttle . I see close to .2 volts and no variation on the wire when throttle is moved from open to closed. This is a brand new controller so I got to believe it's not defective. Is this a valid test or does the white wire signal rely on the electronics in the controller. Help & thanks in advance.

Rick

It's a valid test, but after connecting, you should check that you've still got 5v between the red and the black.

I also suspect the 5v, either in or out, has a poor contact.