Temperature Gauge Failure

I Have A 94 Lt1 Caprice, And Ever Since I Changed The Ignition Module, The Temperature Hand Doesn't Work. The Green Wire Has Power Coming From It, But The Hand Doesn't Move No Matter What. Right Now The Green Wire Isn't Hooked Up To Anything, It's Just Hanging Under The Dash, But It Still Has Power Coming To It And If I Ground It The Temperature Hand Moves. So I Need To KNow Exactly What I Need To Do.:banghead:

Connect the wire to the temperature sending unit. The unit will present a resistance to ground based upon the coolant temperature, causing the gauge to display a relative temperature indication.

The CTS already has the green wire coming from it, the other end was connected to the ignition module. But I've since switch the ignition module out and i didn't think it would make a difference to put it back up to it, because it's a purple wire i didn't connect back to it and the car still start up fine. Since yesterday i've put another CTS on the car and now the temperature hand stays between cold and medium, it doesn't move.