If you are troubleshooting a 16 valve Brick the only useful diagnostic tools are a 12volt LED and the instrument cluster. That fancy doodad is just $119 of wasted cash. It will not do anything that you can't do with an LED, a wire, and the high temperature idiot light in the cluster.
With those simple tools you can:
-read and clear ABS fault codes
-read and clear Motronic fault codes
-set the throttle position sensor zero
On the 16 valve Bricks, these are the only functions available through the three pin diagnostic connector.