It's possible, he couldn't "communicate" with your computer......several things can cause this.....on pin #16, there should be battery voltage....if there is none, the circuit fuse has to be checked.....Pins 4 & 5 are grounds.....if #16 is ok, a test light will light if 16 is paired with 4 or 5....if it doesn't, circuit is open....Pin #2 is the Class II serial data line....this is where the data comes from.....if this is open, grounded, or shorted to voltage, no communication......with a voltmeter attached between 2 and 4 or 5, should see a varying voltage......
One more possibility, is one or more of those pins in the ALDL 16 pin connector could be too wide(some people probe these things with the improper tool) and when the scan tool is attached, there is a bad connection....
First thing to check is battery voltage on #16....